The matters of strict monotheism, circumcision and insistence on no pork in the dining room pretty much forced the Romans to distinguish the Jews, Jesus and his followers included, from run-of-the-mill devotees of Isis, Cybele, or the Rider God. The Empire had a serious beef with Druidism, and the effort to destroy it was successful.
Yes, Jesus arrested and executed as an anti-Roman seditionist seems most likely, at least to me.