San Marco was founded in 1267 by the Silverstrine monks, an Order of the Benedictine Reformed. Over the following 150 years, Florentines became disillusioned with the monks's less than proper religious conduct and, in 1418, pleaded with the Pope to remove the monks from the monastery (which he did). It was only until 1437 that with Cosimo il Vecchio's intervention and persuasion that the Pope finally sent an invitation to the Dominican monks of Fiesole to move into the vacated convent.
The new inhabitants found the structure in deplorable conditions partly because the disgruntled Silverstrine monks striped the church and convent of all its worldly goods, and in part, due to a fire years earlier which destroyed sections of the structure. This was the first of many restorations and “redecorating” the church was to undergo over the coming years.The first to work on the structure was Michelozzo, who was not only Cosimo’s favorite architect but also an artist faithful to the Renaissance innovations created by Brunelleschi. His work consisted of structural interventions: the chapel was extended with the addition of a new apse and a redistribution of the interior spaces, while in the aisle walls were constructed which would eventually support two altars (one for Saint Thomas Aquinas, and another for the Holy Cross.)