Williams endured a shock defeat to Kerber at the Australian Open in January but there was to be no repeat on Centre Court as she edged a thrilling contest 7-5 6-3.
The world number one is now tied with Steffi Graf at the top of the open era women’s champions list and just two short of Margaret Court’s all-time record of 24 titles.
After sealing victory with a forehand volley, Williams dropped her racket and fell outstretched on her back before rising to meet Kerber in a warm embrace.
She has now won 22 of her 28 grand slam finals and also moves level with Graf on seven Wimbledon triumphs, joint second in the open era behind Martina Navratilova’s nine.
Winning 22 slams seemed inevitable when Williams was crowned champion here 12 months ago but three surprise defeats in Flushing Meadows, Melbourne and Paris had prolonged the wait.
“It’s been incredibly difficult not to think about it,” Williams said.
“I had a couple of tries this year, against two great opponents, one being Angelique. It makes the victory even sweeter to know how hard I worked for it.”
Kerber had played the match of her life to beat her prestigious opponent in Australia just 161 days ago and she was a valiant competitor again, the scoreline hardly doing justice to the part she played.
“I would like to say congrats to Serena,” Kerber said.
“You really deserved the title, you’re a great champion and it’s always an honour to play against you in the finals. We played a great match, you deserve it so well done.”
Many suspected Kerber’s most recent victory might be a one-off but the world number four, who will rise to number two after this tournament, had been ruthless in these championships, bidding to become the first German Wimbledon singles champion since Graf, her friend and mentor, beat Arantxa Sanchez Vicario 20 years ago.
Williams had beaten Elena Vesnina in just 48 minutes on Thursday but Kerber made an early statement of intent with a driving backhand winner on the very first point.
It roused the crowd, which included former champions Billie-Jean King, Martina Hingis and Navratilova sitting in the Royal Box, plus pop star Beyonce who was accompanied by her husband Jay Z.
There was an even greater cheer when Kerber registered her first game after withstanding some early pressure on serve.
Williams had clearly done her homework. Two exquisite drop-shots suggested she was not prepared to let her opponent sit behind the baseline, where her powers of retrieval had proven so effective in Australia.
And she was also fired up. After finishing one superb exchange at 3-3 with a crisp forehand volley, the top seed pumped her arms and roared in delight.
Kerber, however, was far from overawed, her slapping forehand a constant menace, to the extent that in the ninth game its force left Williams crumpled on the grass.
The pressure though proved too much at 6-5, as a Kerber backhand gave Williams two set points and the American capitalised on the second with a whipping backhand out wide.
Kerber was once known to fade under the stress of adversity but if anything, she began the second set with even greater vigour, a booming backhand and then forehand pass both sending the crowd into frenzy.
She earned her first break point of the match at 3-3 but Williams stamped out the threat with two aces, the second clocking 124 miles per hour, six miles per hour faster than Andy Murray’s first-serve average against Tomas Berdych.
Just as in the first set, the battle was fierce, one point leaving both players flicking the ball back and forth at the net with Williams again falling to the floor.
Kerber won it but lost the game, broken from 4-3 to leave Williams serving for the match. She finished it to love, a forehand volley confirming victory before she released her racket and dropped to the grass as champion again.