Which preposition to use with roumelia

in Occurrences 1%

The annexation of Eastern Roumelia in 1885 was a great step in the direction of its realization.

to Occurrences 1%

Under this memorable instrument, which dashed to the ground the racial and national aspirations of the Bulgarians which the Treaty of San Stefano had so completely satisfied, their country was restricted to a "tributary principality" lying between the Danube and the Balkans, Eastern Roumelia to the south being excluded from it and made an autonomous province of Turkey.

with Occurrences 1%

This breach in the political life of the race was healed in 1885 by the union of Eastern Roumelia with Bulgaria; and the Ottoman sovereignty, which had become little more than a form, was completely ended in 1908 when the ruler of the enlarged principality of Bulgaria publicly proclaimed it an independent kingdom.

Which preposition to use with  roumelia