Are there any Jews that became Muslims and why?

Answer 1

Of course there are. The majority of Jews who are converting to Islam currently are doing so because they find in Islam a spirituality or Truth that they do not find in Judaism, for whatever reason.

Historically, it was more of a mixed bag. It depends on where the conversion took place and the individual converting. Of course, while the noble reason for conversion still existed, there were also rare forcible conversions and more common attempts to escape Dhimmi Status.

Forcible Conversion

As to the claim of forcible conversion even between sects of Islam, there is quite a bit of evidence to show that this did occur. It was never the dominant form of conversion to Islam, but it existed. There are those perpetrated by the Almohads throughout their Empire. 120,000 Muslims were killed in addition to Jews and Christians in the city of Marrakesh alone due to their "incorrect belief". There were also minor pogroms, such as the one in Cordoba which forced Maimonides to flee Islamic Spain or events like the 1834 Massacre in Safed.

To Escape Dhimmi Status

The Dhimmi, or non-Muslim under Muslim occupation (which included Jews) was required by Islamic Law to pay a number of taxes that were connected with his Dhimmi status. The most famous was the jizya, which was a tax that Dhimmi had to pay for Muslims for the right to not be killed where they stood for not acknowledging Mohammed's Prophecy; it was a form of humiliation. Additional taxes included the kharaj, which was a tax on non-Muslim land-holdings in the Muslim World. The kharaj was so untenable that most Dhimmi were forced to live in the cities where the tax would not be applicable. The above answer is also incorrect as concerns justice. On paper, a Christian or Jew could testify against a Muslim, but in reality, such testimony was not acceptable and the attempt to defame a Muslim would receive retribution. Christians and Jews were not allowed to build new houses of worship, restore old houses of worship, proselytize in any way (this included religious debate or dialogue), or allow wine or pigs to be shown in public.

If such a person converted to Islam, all of these inequalities would drop away. Islamic States have historically created a set of benefits that only Muslims could partake, making a choice to be Muslim tied to choices about economic viability (which trades you could work - especially in government) or tied to choices of social standing. These would strongly weight the choice and produce a steady stream of converts by their very nature.