While some Jewish craftsmen lived in Lithuania since 14th century the number of Jews peaked in 19th century after Russian czar designated Lithuania one of the few Imperial lands where Jews would be allowed to settle. At that time the Jews were primarilly businessman, controlling some 80% of the country's small businesses and 90% of large businesses in mid-19th century. Nearly all Jews were urban dwellers and they were the majority in a few towns and significant minority in many others. In 1880s-1930s town Jews were moving to cities; great numbers emigrated (primarilly to South Africa, Palestine and the USA) decreasing the overal Jewish population in Lithuania.
Subsequently the Jewish community was greatly hit by the Nazi German occupation and its Holocaust (1941-1945). The remaining Jews have largely emigrated to Israel.
Historically the Lithuanian Jews, known as Litvaks, spoke Yiddish, but with the Soviet occupation many switched to Russian in 1970s. Currently a new switch to Lithuanian is taking place. The only seccular Jewish school in Vilnius chose Lithuanian as the medium of instruction (the sole religious school offers education in both languages). Less than 10% of Lithuania's Jews now speak Yiddish natively, the majority of them elderly. 66% declared Russian to be their native language in 2001 census (this percentage is second only to the ethnic Russians).
A dysproportionally large number of Lithuania's Jews collaborated with the Soviet occupational authorities, with 30,6% of Lithuania's communist party members in 1940 being Jewish. Religion, shunned by the communists, also lost ground: according to the 2001 census only 25% of Jews profess Jewish faith with the majority of Lithuania's Litvaks being atheists (the biggest atheist percentage among all ethnic communities).
Thus there are similarities between modern Jewish minority and the Russophone community in their linguistic, irreligious and political preferences.
The widespread atheism causes friction between Jewish religious and seccular (ethnicity-based) communities over who are the descendants of interwar Jewry and should be entitled to receive back the real estate nationalized by the Soviets and related compensations.
1923 census ennumerated 153 743 Jews in Lithuania (excluding Vilnius region), or some 7,1% of the entire population (the share was decreasing). It is estimated that by 1939 Lithuania had up to 200 000 Jews (including Vilnius region). The 1959 Soviet census found 24 672 Jews in the Lithuanian territory (a decrease of 88%, most of it attributable to the German genocide, some of it to succesful emmigration and some to Soviet expulsions). Due to emmigration to Israel this number further shrunk to 12 392 in 1989 census (-50%), to 4 007 in 2001 Lithuanian census (-68%) and to 3 050 in 2011 census (-24%).
Currently there far more people of Litvak origin outside Lithuania than inside; 70% of the South Africa's 85 000-strong Jewry alone have Litvak origins.