Žagarė (Zhager in Yiddish) had one of the oldest Jewish communities in Lithuania. There was a continuous Jewish presence in Žagarė from at least the16th century until October 1941. In its heyday Zhager was known as a city of Torah and wisdom; it produced famous scholars, writers, and rabbis. Chachmei Zhager they were called: the wise men of Zhager. As Josef Rosin notes, while quite a small town Zhager "produced a long line of erudite men, intellectuals, writers, researchers and public figures who were well know in the Jewish world."
For much of its history, the Jewish community comprised a very significant share of Žagarė's total population. In 1766, 840 Jews lived in Žagarė. The Jewish population grew to over 2,200 in 1847, and to approximately 5,500 in 1897 when they constituted 60 percent of Žagarė's total population. By1923, at the tail end of the brief Golden Age of Lithuanian independence, there were about 2,000 Jews in Žagarė, 40 percent of the overall population. By the beginning of World War II the number of Jews declined to about 1,000; most were shopkeepers, artisans, or vegetable gardeners. Today there are approximately 3,000 people in Žagarė; the only surviving Jew, Isaac Mendelson, died in 2011.