Ideas are powerful. Ideas have influence, incite passion, and can capture the imaginations of millions of people. Ideas can take what people only dream of and turn it into reality. The Ottoman Empire and the Catholic Monarchs of Spain were aware of this power. The Ottomans brought an end to the Byzantine Empire by conquering Constantinople in 1453, and the Catholic rulers Ferdinand (1452-1516) and Isabella (1451-1504) completed the conquest of southern Spain against the Muslims in 1492. These rulers asserted their dominance and visions by using the ideologies of Islam and Catholicism respectively, through redeveloping urban environments they had conquered and destroyed, then constructing and reorienting new sacred spaces. These powers used sacred spaces, public spaces, and policy to demonstrate that their singular ideologies were dominant over those of the previous rulers they conquered.
The background and importance of socioeconomic policy on inclusion must be understood before delving into the ideological component of the Ottoman Empire crucial to establishing its presence in the conquered areas. The Ottomans were descended from border warriors, known as ghazis, who wouldlater come together under the leader Osman (1258-1326), the legendary founder of the Ottomans. These warriors close to the eastern walls of Constantinople besieged the walls to no avail, until 1453, when, under the reign of Sultan Mehmet II (1432-1481), the Ottomans defeated the Byzantines and their allies, effectively ending the Byzantine Empire. A shell of its former self even before Mehmet had conquered the city, the Ottoman Empire made it a part of its policy to attract migrants to Constantinople. Using a policy of repopulation, Sultan Mehmet II brought in Jews and Christians, Armenians and Greeks, all in the hope of using the skills each group possessed for the sake of economic benefit. The textile manufacturers found among the Jewish peoples, the naval savants among the Greeks, and the commercial tradesmen among the Armenians helped trade reach places such as the Safavid Empire of Persia and the Venetian State of Italy.1
Policies of tolerance were not an anomaly in Islamic cultures. In fact, it was the rule of most Islamic caliphates and kingdoms up until that time. Islam tolerates People of the Book, which include Jews, Christians, and Zoroastrians. These People of the Book were expected to pay a poll tax in exchange for living under the protection of an Islamic ruler.2 These economic and political policies were indicative of a trend captured within the studies of the “Antagonistic Tolerance Project.” This project is an academic “concept developed to explain long-term patterns of relationship between members of groups that identify themselves and each other as Self and Other communities, differentiated primarily on the basis of religion”.3 Using the ideas of the Antagonistic Tolerance Project, we will be able to see how built environment easily led to urban segregation based off of culture, creed, and the built environment, aptly expressed through the religious institutions and architecture of mosques and churches that would spring up in the Constantinople crafted in the Ottoman image.
Sultan Mehmet II made it clear that a new ideology was taking over from the old Greek Orthodox Christianity of the Byzantine Empire. The way that Mehmet made this apparent was by modifying Hagia Sophia, the great church at the heart of Orthodox Christianity in Constantinople. He commissioned Hagia Sophia to be turned into a Muslim house of worship known as a mosque, renaming it Ayasofya. By constructing minarets and a religious school—a madrassa—Mehmet took one of the most visible signs of Constantinople and made it the beacon of his new vision for all his subjects to see.4 Ottoman Muslims also took Hagia Sophia’s smaller counterpart, known simply as Little Hagia Sophia, and turned it into a mosque. 
Once a church used to support a Monophysite community taken in by Byzantine Emperor Justinian and his wife Theodora, this Christian church became reoriented just as its larger counterpart was.5, 6 Demonstrating what the new dominant ideology would be in terms of how the Ottoman state presented itself, there were other mosques built at this time, most notable among them being the Faith Mosque to mark Mehmet’s victory.7 The conversion of these built environments once in use for Christianity validated exactly what ideology the Ottoman Empire would be associated with.
Hagia Sophia and its smaller counterpart are only one aspect of the “radical reorientation” Sultan Mehmet II was creating in Constantinople. Other old churches and convents were also being converted or demolished. An old Byzantine church became the mausoleum of Ayyub al-Sansari (567-672/674), a venerated Muslim saint.8 New religious centers were also constructed including lodges for Muslim mystics, known as Sufis, and the kitchens and hospitals that were built for Muslim holidays and general use.9 Later, laws would be passed that made it so Christian and Jewish religious buildings could not be taller than mosques. An example of this would be of Saint Antoine’s Church on Istiklal Avenue. Built on a lower level than the street and moved back from view, Christian communities would no longer have a magnificent church like Hagia Sophia. While laws such as these would make it difficult for Jews and Christians to express themselves through sacred space, their presence in other, more secular sections of the built environment would be an example of the conditions tolerance can produce.
While there would not be any churches or synagogues as grand or magnificent in the foreseeable future as the Ottoman mosques, Jews and Christians made up for it by occupying public space and obtaining lawful rights. Once the Ottomans had replaced the Byzantine Empire, Jews found themselves to have more freedom, coming from Spain and across Eastern Europe to establish a cultural and commercial presence in Constantinople. Muslims, Christians and Jews were barely segregated from each other at the Bazaar or in residential neighborhoods. While certain neighborhoods could revolve around a mosque or synagogue, Jews and Christians could be seen to live right next door to Muslim neighbors.10 Intermarriage was even allowed between Muslims and non-Muslims, due to marriage being more of a practical than religious alliance.11 Through the conversion of churches into mosques and the highlighting of Islam in Ottoman society by building Dervish lodges and instituting laws on the height of non-Islamic religious buildings, the Ottoman Empire was able to bring the ideological lynchpin of Islam into the spotlight. But it was also through Islam that the Ottomans accepted their Christian and Jewish counterparts, and through this tolerance these groups were all able to find a degree of harmony. 
The campaign of Christianity over Islam on the Iberian Peninsula began centuries earlier as the Reconquista. Eventually, by 1236, Ferdinand III of Leon and Castile (1199-1252) was able to take Cordoba, once a beacon of social progress throughout Medieval Europe, from the Muslims. While this did not initially induce great change, the Catholic Church and its local supporters sought to make their mark. Jewish subjects were given freedoms that were relatively similar to the ones they had under Muslim rulers, but those were slowly taken away as restrictions were put in place.12 We see these types of restrictions extended beyond the reign of Ferdinand and Isabella. Laws prohibiting Jewish culture and worship are made evident through a hidden synagogue found on a side street in Cordoba. The original Hebrew in the synagogue and menorah were hidden behind walls disguising it as a Christian house of worship, indicating the differences taking shape in a city once shared by Christians, Jews, and Muslims. The identity of Jews and their rights to practice were being taken away, with many Jews suffering in Cordoba and under the rule of Ferdinand and Isabella two centuries later.
Jews were not the only group to have to their house of worship modified. Cordoba has much more to show in the way of religious reorientation when it comes to its sacred spaces. When the city was the capital of Abd al-Rahman (731-788), the founder of the Umayyad Dynasty of al-Andalus (the Muslim section of the Iberian Peninsula), the mosque of Cordoba, known as the Mezquita, was a symbol of the capital’s greatness. Built on top of an old Visigothic church exhibit which was in control of the city, it contains a courtyard, minaret, and columns connected by keyhole arches. Muslim art was displayed in the intricate design and meaning of the mihrab, the place within a mosque that informs worshippers of the direction of the holy city of Mecca. The reason why the Mezquita held importance centuries ago, as it does now, is because it is a testament to the dominant Islamic ideology in al-Andalus. The ever-expanding size, wealth, and splendor of the mihrab display the power and continuing magnificence of the Muslim presence. Christians themselves saw how this presence was expanding as the mosque was enlarged and given greater prominence, and they revolted against their Muslim rulers in 848.13
However, the presentation of wealth and political dominance within the sacred space of the Mezquita was not forgotten. In later centuries, after the Christians had conquered Cordoba, the mosque continued to be a focus of the dominant ideology. 
Where Islam was once a visible force, Christianity would now replace it. Building the cathedral in the Mezquita was a continuation of Cordoba’s myth as “the center of a powerful, apparently invincible culture.” The Catholics who conquered the city understood the power such a symbolic building could wield. The cathedral itself would occupy a central position in the Mezquita, with the walls and ceiling painted all white. Known as Catedral de Santa Maria, it started in 1523 a few decades after Ferdinand and Isabella had taken Granada. Built during a time when the success of the Reconquista covered most of the Iberian Peninsula, the dominance of the Catholic ideology was in full force. Due to this, the magnitude of the cathedral would reflect the power of Catholicism at that time in Spain. There would be figures of saints and angels carved into the walls and covered with gold leaf, and scenes from biblical stories carved into large wooden chairs. Just as the mosque represented the invincible spirit of Islam before the Catholics conquered Cordoba, it would do the same for Catholicism after the Muslims were expelled.14
There was another aspect of the cathedral inside the Mezquita reflected in other buildings of conquest, particularly in Granada. Since the Umayyads had taken Spain in 711, there had been ups and downs in power and the way it was divided throughout al-Andalus. From the Umayyad Caliphate of Cordoba (929-1031) to the Taifa Kingdoms (1011-1238) and the Almohad Dominion (1121-1269) and other forms of governance such as the Nasrid Dynasty of Granada (1232-1492), the Muslims held onto power as best they could before Ferdinand and Isabella of Castile and Aragon took Granada in 1492.15 Once again, the diversity that existed in Muslim society would be replaced by a dominant Catholic ideology that would purge all competing ideologies. This would be carried out by forced migration of Jews and Muslims through persecution and Inquisition trials that sought out any disingenuous conversos, Jews and Muslims that converted to Catholicism to keep their property.16, 17 Even as these societal measures were being carried out, the built environment would soon change in Granada, leaving no allusions as to what ideology would be dominant under the reign of Ferdinand and Isabella.
The Cathedral of the Annunciation is a Renaissance-style cathedral that rises above the roofs of Granada. This church is as grandiose in its display of the saints and royal emblems on the exterior as in its presentations of Jesus Christ on the inside. Containing around two to three different churches within its building, as well as a royal chapel housing the tomb of Ferdinand, Isabella, and their children, the Cathedral and its art makes it clear that the singular vision of Catholicism was what these monarchs desired for Granada. The cathedral itself is a beacon of Catholic ideology in a city once populated with mosques and minarets later converted into 
churches and bell towers. Yet, it is the height of the church that truly makes it an important building within the environment. Catholic churches typically used vaulted ceilings to give a sense that they were reaching for the perfection of Heaven; the Cathedral of the Annunciation was no exception. What this has created is a distinct sense of verticality possessed by the building, interpreted by the Antagonistic Tolerance Project as a way an area is dominated by a certain identity or ideology.
When discussing how Catholic churches reach far into the sky as though reaching for Heaven, what is really being discussed is the verticality of the building. To discuss verticality in this paper, the best examples to use are the Mezquita and the Cathedral of the Annunciation. The cathedral within the Mezquita rises noticeably higher than its surroundings within the mosque. This verticality, coupled with the clear white color and gold figures that make the cathedral decidedly different from a mosque structure, seeks to make the cathedral the new focal point of the expanded mosque. The verticality of the Cathedral of the Annunciation is used in the same vein, as a way to differentiate itself from the surrounding city and any aspect of the built environment left over from the Muslims. This concept was not lost on the Ottomans either. Mosques are buildings that are usually more horizontal than vertical in design, but the Blue Mosque proves that verticality can still be employed even with the use of a dome. The Blue Mosque was built in the 17th century, and it was the first Ottoman mosque to be commissioned by the government in over four decades. Known better as the Sultan Ahmet Mosque after the Ottoman ruler who commissioned its building, the mosque is situated right across from Hagia Sophia, both dominating the skyline with their enormous domes. With the roof comprised of smaller domes until it reaches to the highest one, the sense of verticality is much more palpable once one enters inside. Within the mosque are large columns which appear to reach to the sky, unlike the domes themselves. With this impression, there is a sense that the Blue Mosque is itself a sort of Heaven on Earth, with a beautiful immensity that can be found nowhere else.18
Verticality is as much an aspect of ideological structures as the centrality of where buildings are placed among the lives of the populace. The public may not always live near buildings of the dominant ideology, but another way that the rulers can make their ideologies known is by putting them in close proximity to public space. The sacred spaces mentioned thus far—the Mezquita, the Cathedral of the Annunciation, Hagia Sophia, and the Blue Mosque—all have close proximity to public spaces in the present day and the past. 
The Mezquita’s courtyard is a space where the public can meet and discuss topics. The Cathedral is located near a small bazaar and a type of public square that is used for public events to the present day. Hagia Sophia and the Blue Mosque are near their own public square of Constantinople, known as Sultan Ahmet Square. Formerly the place where the Hippodrome of Constantinople was located, the proximity of the mosque and church to the former royal center makes their looming edifices clear to the public of the city and any outsiders who may find themselves there.19
By employing verticality and centrality with their ideological buildings, the Catholic Monarchs made it clear that their new society would revolve around a single ideology—Catholicism. The central dominance of Catholicism was used as a way to craft a vision that was in line solely with the Catholic faith, a vision that would not tolerate interference from Judaism, Islam, or any person they believed to be feigning their Catholic beliefs. The centrality and dominance of Islam in the Ottoman Empire expressed through the new mosques of Constantinople, converted sacred spaces, and laws restricting how churches and synagogues were built did not impose such an order. Instead, for all the dominance the Ottomans wanted to express through Islam, their ideology still allowed for leniency and tolerance. Antagonistic Tolerance was expressed in two very different ways that contributed to different destinies for each society. 
These monarchs not only made it a matter of policy, but the built environment was the realization of their ideological visions, the main method by which they asserted their ideologies. Whether it was how these sacred spaces were oriented towards the public or reoriented from their original ideological purposes, the built environment made it clear the faith and visions of the monarchs would be the ideas and religions to dominate the lives of their subjects.
References
Bardill, Jonathan. "The Church of Sts. Sergius and Bacchus in Constantinople and the Monophysite Refugees," Dumbarton Oaks Paper 54 (2000): 1-11. Print.
Dodds, Jerrilynn Denise. "The Great Mosque of Córdoba." The Art of Islamic Spain. New York: Metropolitan Museum of Art, 1992. 11-25. Print.
Goffman, Daniel. The Ottoman Empire and Early Modern Europe. Cambridge, U.K.: Cambridge University Press, 2002. Print.
Hayden, Robert. "Contested Sharing." Contested Sharing. University of Pittsburgh, 2011. Web. 3 July 2013. http://www.ucis.pitt.edu/antagonistictolerance/Contested_sharing.html.
Hillenbrand, Robert. "'The Ornament of the World': Medieval Cordoba as a Cultural Center." The Legacy of Muslim Spain. Ed. Salma Khadra. Jayyusi. Leiden: Brill, 1992. 112-35. Print.
Kafescioglu, Cigdem. "Between Edirne and Konstantiniyye." Constantinopolis/Istanbul: Cultural Encounter, Imperial Vision, and the Construction of the Ottoman Capital. University Park, PA: Pennsylvania State University Press, 2009. 16-52. Print.
Phillips, William D., and Carla Rahn Phillips. A Concise history of Spain. Cambridge: Cambridge University Press, 2010. Print.
Endnotes
1 Daniel Goffman, The Ottoman Empire and Early Modern Europe (Cambridge: Cambridge University Press, 2002), 33, 47, 68-69, 85-86.
2 Dr. Pinar Emiralioglu, February 7th, 2013 Lecture, History of the Ottoman Empire (University of Pittsburgh, 2013).
3 Robert Hayden, Contested Sharing, http://www.ucis.pitt.edu/antagonistictolerance/Contested_sharing.html.
4 Cigdem Kafescioglu, Between Edirne and Konstantiniyye: The City's First Ottoman Years, Constantinopolis/Istanbul: Cultural Encounter, Imperial Vision, and the Construction of the Ottoman Capital (Penn State Press, 2009), 18-20.
5 Monophysites believe the dual divine and human natures of Christ were of one single nature, instead of Christ being bother containing two totally separate natures at once.
6 Jonathan Bardill, "The Church of Sts. Sergius and Bacchus in Constantinople and the Monophysite Refugees," Dumbarton Oaks Paper 54 (2000), 1-11.
7 Kafescioglu, 18-22.
8 Ibid, 48.
9 Emiralioglu.
10 Goffman, 90-91.
11 Emiralioglu.
12 Robert Hillenbrand, "'The Ornament of the World': Medieval Cordoba as a Cultural Center," in Salma Khadra Jayyusi, ed., The Legacy of Muslim Spain, vol. 1 (Brill, Leiden, Netherlands, 1992), 128.
13 Ibid, 132-133.
14 Jerrilynn D. Dodds, "The Great Mosque of Córdoba," in Jerrilynn D. Dodds, ed., Al-Andalus. The Art of Islamic Spain (Metropolitan Museum of Art, NY, 1992), 24.
15 William Phillips, Jr., and Carla Rahn Phillips, The Rise of Spain to International Prominence, A Concise History of Spain, (Cambridge, Cambridge University Press, 2010), 98.
16 Alhambra Decree was a factor in expelling the Jews from Spain in 1492. Due to this persecution, most Spanish Jews migrated to Constantinople where they would find a more tolerant environment.
17 Ibid, 100.
18 Cengiz Haksoz, May 23rd, 2013 Lecture, History of Conquest (University of Pittsburgh)—I know there is no need for disclaimers, but I do want to point out that Cengiz's lecture in the ISA classroom on this day was immensely helpful in organizing my argument on sacred space and the different ways to analyze it. His work with Dr. Hayden that he communicated to us during that morning was very beneficial to my essay. I cannot stress that enough.
19 Ibid.
20 All photos included with this article were taken by the author.