The term 'Palestine', according to my dictionary, comes to us from Arabic 'Falastin', which in turn comes from the term 'Philistine', a sea-faring, non-Semitic (language) group of people who established city states on the coast and adopted the Semitic (but non-Arabic) language and religion of the area. In ancient times, they were absorbed into the Kingdom of Israel under King David (about 1000 BC).
The area called Palestine has been ruled over by Muslim Arab (636 AD) and Muslim Ottoman (1516) empires. Turkish rule of Palestine and Arabia ended in WW I (see the movie 'Lawrence of Arabia' for some technicolor background).
When the Zionist movement arose in the 19th century, Arabs were the linguistic and cultural majority in Palestine. Jewish immigration and Arab exile during the past 100 years are the two related processes that have given modern day Palestine a Jewish majority in the area co-extensive with what is now the state of Israel.
BTW, one important reason why Zionists committed acts of terrorism against the British in Palestine was the immigration restrictions in place after WW II.
In any chauvinisti or racialist argument over who is more 'authentic' in the area, there is bound to be confusion of cultural, linguistic and religious groupings. Arabic--a language or culture--is not the original Semitic language of Palestine. Hebrew could be said to be an original Semitic language of what is now Palestine, but it is not the only one (but the other ones, such as Caanite or Phoenician, are extinct). Hebrew was largely an extinct language, kept alive only for religious purposes--until the modern revival of the language in Zionist Palestine and then the state of Israel.
Yours, Charles Jannuzi Fukui University, Japan