Аннотация:Abstract This study weighs the evidence for Leonardo Bruni's estrangement from the emerging Medici party (from the 1420s) and the Medici regime (from 1434). Bruni had ties to both the Mediceans and their oligarch opponents, although ties with the latter appear to be stronger, particularly in terms of Bruni's humanist relations. While Bruni stayed on as Chancellor of Florence when the Medici took over in 1434, some recent studies suggest that the Medicean government was making things difficult for him. The study finally reproduces a report from the Milanese Chancery of 1437 stating that Bruni will support a rebellion in Arezzo against Florence, which will result in the "destruction and ruin of the Florentines."