It actually started with WW1 when Britain promised both Jews and Palestinians their own state if they overthrew the Ottomans.
Before that, Ottoman rule was oppressive to both groups relatively equally for a few hundred years.
WW2 and the whole holocaust thing just turned it from a small problem into a big problem, as millions of European Jews sought a safe haven outside of Europe, leading to the creation of a religious ethnostate in 1948.
So yeah, Europeans definitely are to blame, but Arabs and Palestinians aren’t innocent either. They rejected a perfectly adequate solution by the UN in 1947.