Antonio I was one of several claimants of the Portuguese throne during the succession crisis of 1580. As the illegitimate grandson of King Manuel I, his claim was considered weak. Managing to secure the throne for just 20 days, he soon suffered a defeat by Habsburg forces and was forced to flee to the Azores, where he ruled in exile while Philip II of Spain consolidated control of mainland Portugal. By 1583, he once again had to flee, this time to France where he continued to advocate for his moribund cause. During his short tenure on the Azores, he asserted his claim by the mintage of coins in his name and the countermarking of older Portuguese issues. Struck during a very short period and often confiscated and destroyed after his defeat, all of Antonio's coinage is quite scarce today.
Estimate: $300 - $500