1 Kings 12:31-33

And that wasn’t the end of it. Jeroboam built forbidden shrines all over the place and recruited priests from wherever he could find them, regardless of whether they were fit for the job or not. To top it off, he created a holy New Year festival to be held on the fifteenth day of the eighth month to replace the one in Judah, complete with worship offered on the Altar at Bethel and sacrificing before the calves he had set up there. He staffed Bethel with priests from the local shrines he had made. This was strictly his own idea to compete with the feast in Judah; and he carried it off with flair, a festival exclusively for Israel, Jeroboam himself leading the worship at the Altar.