[1][2][3] Gábor Ágoston calls this a treaty or truce, but defines its nature as mere "verbal promise" (correspondences between Ferdinand and his envoy also show the agreement as a matter between Suleyman and the king).
[6] Two claimants emerged: Ferdinand I, the archduke of Austria; and János Szapolyai, the voivode (governor) of Transylvania (Turkish: Erdel, now the west of Romania).
Although Szapolyai was backed by most of the Hungarian elite, Ferdinand declared himself the legal king of Hungary, with the support of his older brother, Charles V, Holy Roman Emperor.
The Ottoman Empire, however, backed Szapolyai, and Emperor Suleyman I mounted a threat against Austria in two military campaigns (of 1529 and 1532).
Suleyman decided to concentrate his activities in the east and to give up his pursuit of hostilities in the west[7] and so the treaty was signed.