When Sigismund of Austria completed his mortgage, in 1469, at St. Omer, and returned home, as already stated, he was fired with zeal to divert some of the dazzling Burgundian wealth into the empty imperial coffers. An alliance between Mary of Burgundy and the young Archduke Maximilian seemed to him the most advantageous matrimonial bargain possible for the emperor's heir. He urged it upon his cousin with all the eloquence he possessed, and was lavish in his offers to be mediator between him and his new friend Charles. Frederic was impressed by Sigismund's enthusiastic exposition of the advantages of the match, and little time elapsed before his ambassador brought formal proposals to Charles for the alliance. The duke received the advances complacently and returned propositions significant of his personal ambitions. As early as May, 1470, his instructions to certain envoys sent to the intermediary, Sigismund, are plain. In unequivocal terms, his daughter's hand is made contingent on his own election as King of the Romans, that shadowy royalty which veiled the approach to the imperial throne. "_Item_--And in regard to the said marriage, the ambassadors shall inform Monseigneur of Austria that, since his departure from Hesdin, certain people have talked to Monseigneur about this marriage and mentioned that, in return, the emperor would be willing to grant to Monseigneur the crown and the government of the Kingdom of the Romans, with the stipulation that Monseigneur, _arrived at the empire by the good pleasure of the emperor_ or by his death, would, in his turn, procure the said crown of the Romans for his son-in-law. The result will be that the empire will be continued in the person of the emperor's son and his descendants. "_Item_--They shall tell him about a meeting between the imperial and ducal ambassadors, at which meeting there was some talk of making a kingdom out of certain lands of Monseigneur and joining these to an _imperial_ vicariate of all the lands and principalities lying along the Rhine." In the following paragraphs of this instruction,[7] Charles directs his envoys to make it clear to Monseigneur of Austria (Sigismund) that the duke's interest in the plan does not spring from avarice or ambition. He is purely actuated by a yearning to employ his time and his strength for God's service and for the defence of the Faith, while still in his prime.