 Although King James rewarded Calvert in 1623 for his loyalty by granting him a 2 @,@ 300 @-@ acre ( 9 @.@ 3 km2 ) estate in County Longford , in the central Ireland region of Leinster , where his seat was known as the " Manor of Baltimore " , Calvert was increasingly isolated from court circles as the Prince of Wales , ( heir to the Throne ) and the first Duke of Buckingham ( George Villiers ) <unk> control of policy from the ageing James . Without consulting the <unk> astute Calvert , the prince and the duke travelled to Spain to negotiate the Spanish marriage for themselves , with disastrous results . Instead of securing an alliance , the visit provoked a hostility between the two courts which quickly led to war . In a reversal of policy , Buckingham dismissed the treaties with Spain , summoned a war council , and sought a French marriage for the Welsh Prince . 
