To what extent were the claims of the Zionists for a homeland valid, up to 1919?

In that the Jews had been without a serious homeland for close to two thousand years such claims would have been valid at most times during that long period. Jews were persecuted in much of Europe for much of the time that they were there. But note that many Jews still live in Europe, and that some of them have risen to the top.

But that whole claim business would also apply to any "people" who had been driven out of their homeland long ago. You could make the same claim for the original inhabitants of Britain and much of Europe before the Roman conquest, or the original inhabitants of the Americas before Columbus blundered into the area.

History happens, invasions and occupations take place.

Wow, so like me, Cacoethes Scribendi is no stooge of the zionists who are so powerful here in the US.

But to answer the question, by 1919 the zionists were backed by the balfour declaration. Britain, which had palestine by then favored creation of a jewish state there. In that sense their claims were "valid."

What has 1919 got to do with anything? Zionism's claims are invalid whatever the year. The fact that a people inhabited a piece of real estate 2000 years ago doesn't give them the right to make any claims on it -- yesterday, today or tomorrow.

To the extent that Jews in Gentile-dominated countries were routinely oppressed and murdered, which is to say, to a very great extent indeed.

no extent whatever

as already said - just cos the jews claim it was theirs 4000 years earlier- so what? (and that assumes it WAS theirs - which I do not believe)

as for being persecuted?

again - so what?