The Ashkenazim were all immigrants or the children of immigrants, and almost none before 1820. Many were there for study and were supported by (and hence dependent on) foreign funds. They generally spoke Yiddish and had a Yiddish influenced pronunciation of Hebrew. They were also not a unified community, but split up by which part of eastern Europe they were from. The Sephardim in Palestine, by contrast, generally had been there for generations. They spoke Ladino and Arabic and were generally in better positions in society. [1, p29] The Sephardic pronunciation was likely the prestige accent.
Arabic was the default language of the cities, and within their enclaves the different groups used their own languages. When Jews of different groups needed to talk to each other, though, they would use Hebrew with a Sephardic pronunciation. [1, p28] As a result, when Ben Yehuda arrived in Palestine he was able to use Hebrew with most of the Jews there. The Sephardic Jews were used to speaking Hebrew with non-Sephardic Jews, and while Ben Yehuda could speak Yiddish he did not let this be known so the Ashkenazim were also willing to speak to him in Hebrew. [1, p31]
The vocabulary of this simplified Market Hebrew was very restricted and used in a roundabout way in an effort to apply it to modern things and the grammar was a hybrid of Biblical and Talmudic Hebrew. Many aspects of the language, especially the vowels and the syntax, varied by speaker as people were influenced by their native languages. [1, p31] This Hebrew is probably properly a pidgin, as it was not a full language but a restricted form used by groups that did not have another common language.
Over the course of the revival, there was a stream of Jewish immigrants from Europe. They are generally treated as two groups, the first and second aliyot4. The first alyiah consisted of about 35,000 Jews immigrating between 1882 and 1903. The second consisted of closer to 40,000 and covers the next ten years, from 1904 to 1914. Both aliyot consisted mostly of young idealistic urban Ashkenazim who had not done any farming before. Upon reaching Palestine most went into farming communities, and the first alyiah suffered much from lack of experience. By the time of the second alyiah started arriving things were more sorted out and the earlier immigrants were more experienced. The semi-isolated farming communities they formed turned out to be excellent for the growth of Hebrew, as they allowed a group of people to together make a switch to a language without needing the wider world to go along with them.