The name Sanballat
is Babylonian; it means Sin (the Babylonian moon god) has given life.
The addition the Horonite
suggests that Sanballat hailed from one of the towns of Beth-Horon (Upper or Lower Beth-Horon, Joshua 16:3, Joshua 16:5), northwest of Jerusalem. Alternatively, he may have hailed from Horonaim in Moab (Isaiah 15:5) or Hauran (Ezekiel 47:16, Ezekiel 47:18). Of the three options, the first is the most likely since further references to Sanballat in the book of Nehemiah demonstrate that this man was familiar with the region around Jerusalem. His Babylonian name suggests allegiance to the Babylonian religion in his upbringing.
10 But when Sanballat the Horonite and Tobiah the Ammonite servant heard this, it displeased them greatly that someone had come to seek the welfare of the people of Israel.