Gustav Weigand in the context of "Imperial German"

The Romanians in Bulgaria (Romanian: români or rumâni; Bulgarian: румънци, rumŭntsi, or власи, vlasi), are a small ethnic minority in Bulgaria. In the country, Romanians live in several northern regions, mostly along the Danube. This includes a region between the city of Vidin and the Timok river; these Romanians form a continuous community with the Romanian community in the Timok Valley of Serbia. Another region with a high density of Romanians is located between the towns of Oryahovo and Svishtov. Another goes from Tutrakan to the Bulgaria–Romania border at Northern Dobruja. There also are scattered groups of Romanians within the interior of Bulgaria, such as in Pleven or around Vratsa. The Romanians in Bulgaria are not recognized as a national minority, and they lack minority rights such as schools or churches in their own Romanian language. Many are subject to assimilation.

In Bulgaria, the local Romanians are commonly referred to as "Vlachs". This term is also applied to the Aromanians of the country, as well as to Romanian-speaking Boyash Gypsies. The German linguist Gustav Weigand dealt in the most detailed and concrete way with the Vlach population south of the Danube. In 1905 he undertook a special trip through Bulgaria to establish where the Vlach settlements are located and to characterize their language. According to Weigand, the largest group of Vlach population moved to the Bulgarian lands in the 1830s, when the so-called Organic statute (1831), was introduced in Walachia, by virtue of which men were subject to mandatory military service. Using the data from the population census in the Principality of Bulgaria in 1900, he pointed out that, at the end of the 19th century, 86,000 Vlachs were registered in Bulgaria, of which 11,708 (about 15%) were born north of the river, which means that they moved south of the Danube in the second half of the 19th century.