 Complete the following phrase:  The Monserrat area traces its origins to the foundation of Buenos Aires itself, when, in 1580, Spanish Adelantado Juan de Garay disembarked on the areas shores. The Fort of Juan Baltazar of Austria, the marginal settlements first, was built in 1594 and, in 1608, newly arrived Jesuits were granted a 2-hectare 5 acre lot, nearby. The Jesuits began work on the Saint Ignatius Church in 1686. Consecrated in 1734, it is the oldest existing church in Buenos Aires. Possessing the finest school and library at the time and offering colonial Buenos Aires only truly classical education there, their property became popularly known as the Illuminated Block. The small citys growing population led to the introduction of a number of other religious orders in this area, notably the Catalan Brotherhood of the Virgin of Montserrat, whose chapel became the neighborhood namesake in 1769. The Cabildo City hall became the scene of the 1810 