Acquisition of Israeli Nationality
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Acquisition of Nationality according to the Law of Return
On the establishment of the State, its founders proclaimed "...the renewal of the Jewish State in the Land of Israel, which would open wide the gates of the homeland to every Jew...." In pursuance of this tenet, the State of Israel has absorbed survivors of the Holocaust, refugees from the countries in which they had resided, as well as many thousands of Jews who came to settle in Israel of their own volition.
The Law of Return (1950) grants every Jew, wherever he or she may be, the right to come to Israel as an oleh (a Jew immigrating to Israel) and become an Israeli citizen.
For the purposes of this Law, "Jew" means a person who was born of a Jewish mother or has converted to Judaism and is not a member of another religion.
Israeli citizenship becomes effective on the day of arrival in the country or of receipt of an oleh's certificate, whichever is later. A person may declare, within three months, that he/she does not wish to become a citizen.
Since 1970 the right to immigrate under this Law has been extended to include the child and the grandchild of a Jew, the spouse of a Jew, the spouse of a child of a Jew and the spouse of a grandchild of a Jew. The purpose of this amendment is to ensure the unity of families where intermarriage had occurred; it does not apply to persons who had been a Jews and had voluntarily changed their religion.
An oleh's certificate may be denied to persons who:
engage in activity directed against the Jewish people;
may endanger public health or the security of the state;
have a criminal past, likely to endanger public welfare.
http://www.mfa.gov.il/MFA/MFAArchive/2000_2009/2001/8/Acquisition of Israeli Nationality
So there you go. Convert and move and you are in!
No big deal, unless you are religious.