You're still lying aren't you....
First of all there barely werent that many christians, most were Jewish tribes and pagan tribes. Especially at the time of Muhammad and the setting.
I already explained what you claim to be a massacre of Jews(total nonsense):
Btw, I see more and more that Jews find Medina to be important to them. But they won't tell why the Jews lost leverage there. For those who don't know there were three Jewish tribes in Medina. Known as Banu Qainuka'a, Banu Nadhir and Banu Qurayza. When Muhammad migrated to Medina they accepted him as the leader and he granted them the famous charter. He taught everyone to be more moderate and temperate in everything. They stopped drinking and gambling and also stopped taking loans at high interest rates from the Jews. Revenue started drying up for them and that's when they were losing economic influence there. They also realized Islam was the enemy of exploitation and a capitalist system. The three tribes agreed to defending the city from a siege as part of the charter. But on 627 they did not contribute any men or resources. This later lead them to being caught conspiring with the enemy for the destruction of the Muslims. They were going to attack from the rear if Amr Ibn Abd Wudd(enemy commander) over took the Muslims. This is when Muhammad allowed the Jews to chose their abitrator. They should have chosen Muhammad as he would have let them depart from Medina, but they made a costly mistake and chose Sa'aad ibn Muadh(leader of former allies). He invoked the Torah scriptures in which Moses ordered all men of the Caanites to be killed and women and children taken as slaves. Just to clarify the facts here, it's not what Jews call it.