Polish ethnic and cultural presence in modern Belarus are an intricate part of its history. The lands of modern Belarus are the birthplace of Mickiewicz and Domejko among others. The proto-Belarusian language, called Ruthenian or Old Belarusian was protected by law in the Polish–Lithuanian Commonwealth and used as local vernacular, while both Polish and Latin languages were the lingua franca of the throne. "As the 16th century drew to a close" – wrote Andrew Savchenko about the local nobles, they had to contend with "an increasingly stark choice: to strengthen their ties with Poland or to suffer disastrous military defeat and subjugation" by the Russian Empire, thus leading to their 'voluntary' "Polonization". After the Napoleonic Wars, Russia annexed the territories of the former Grand Duchy of Lithuania as its North-Western Territory. Throughout the 19th century, a majority of the gentry, which comprised about 10% of the population, continued to identify as culturally Polish. But "the mass of unassuming peasants", ethnically Lithuanian or Belarussian, "was subjected to active Russification" by the Tsarist authorities including the abolition of the Uniate Church created by the Union of Brest, a uniquely Belarusian institution and a cornerstone of the Belarusian nation.