I know it is year 5769 in the Jewish calender. What happened in year 0?

Nothing. According to them, God, our creator, created the World. The Jews only stopped with the Old Testament while we have the Gregorian Calendar and we believe, that Jesus was born and therefore, also, believe in the New Testament. For the Jews, the Messiah hasn't come yet. The year number on the Jewish calendar represents the number of years since creation, calculated by adding up the ages of people in the Bible back to the time of creation. However, this does not necessarily mean that the universe has existed for only 5700 years as we understand years.

And by the way, the spiritual Patriarchs of Judaism are: Abraham, Jacob and Isaac.

n the fourth century, Hillel II familiar a fastened calendar in step with mathematical and astronomical calculations. This calendar, nevertheless in use, standardized the size of months and the addition of months over the direction of a 19 12 months cycle, so as that the lunar calendar realigns with the image voltaic years. Adar I is further interior the third, 6th, 8th, eleventh, 14th, seventeenth and nineteenth years of the cycle. the present cycle began in Jewish 12 months 5758 (the 12 months that began October 2, 1997).

I believe the first year of the Jewish Calendar was when Abraham spoke to God.

Apparently nothing.

http://www.uwm.edu/~corre/calendar.html

The world exponentially became a much more horrible place to live in.