Which preposition to use with margarita

in Occurrences 1%

They looked, and craned, and murmured comments until the señora appeared, a little breathless and warm from her last conference with Margarita in the kitchen, and turned their tongues upon the festival.

of Occurrences 1%

In order to enforce compliance, Bolivar invested Carthagena, before which he remained a considerable time, when he heard of the arrival at Margarita of General Morillo, with ten thousand Spanish troops.

Which preposition to use with  margarita