As far as I’m concerned:
1. Babe Ruth and Roger Maris (depending on length of season) hit the most home runs in one year.
2. Hank Aaron was, and is, the Home Run Lifetime Champion.
There were some others involved, I forget their names, but they don’t even warrant an asterisk.
He wasn't a slugger in the classic sense, and benefitted a lot from playing in small ballparks. I always thought his career home run total made it easy to overlook other parts of his game. He had a higher lifetime batting average than Pete Rose, and would have had more than 3,000 career hits even if you never counted any of his 755 home runs!