Why did Russia slaughter Jews and let them immigrate to Palestine?

188 1 In March, after the assassination of Tsar Alexander II, Russia tried to cover up class contradictions, diverted attention and provoked a frenzy of massacre of Jews, and countless Jews were massacred. 1842 in may, Russia also issued a decree to drive Jews out of villages and residential areas. In this way, Jews began the first wave of immigration to Palestine, and established some Zionist settlements, and the Zionist movement initially rose.