Williams had been chasing Steffi Graf’s milestone since she won her 21st major tournament here last year but surprise defeats at the US, Australian and French Opens prolonged the American’s pursuit.
The wait came to an end on Centre Court, however, as Williams edged a thrilling final 7-5 6-3 against Kerber to tie Graf at the top of the Open-era list and clinch her seventh Wimbledon crown.
The day got even better when Williams returned to Centre Court to win her second title of the day as she and sister Venus triumphed in the doubles final.
“It’s obviously a great relief,” Williams said. “I’ve definitely had some sleepless nights, if I’m just honest, with a lot of stuff.
“Coming so close. Feeling it, not being able to quite get there. My goal is always to win at least a slam a year. It was getting down to the pressure.”
Williams was denied a calendar grand slam in Flushing Meadows by little-known Italian Roberta Vinci before slipping up to Kerber in Melbourne and then Garbine Muguruza in Paris.
It meant the world No 1 arrived at the All England Club on the back of three successive disappointments, and with questions to answer about her conviction and self-belief.
“I’ve just felt a lot of pressure, I guess. I put a lot of that pressure on myself,” Williams said.
“Obviously I had some really tough losses but if you look at the big picture, I was just thinking about getting to three finals, grand slam finals.
“I had to start looking at positives, not focusing on that one loss per tournament which really isn’t bad and for anyone else on this tour they would be completely happy about it.
“Once I started focusing more on the positives, I realised I’m pretty good. Then I started playing a little better.”
Williams has lost only six of her 28 grand slam finals to date and stands only two major triumphs short of Margaret Court’s all-time best 24.
Is Court’s mark now the target? “Oh God, no,” Willams said. “I’ve learned a lot about 22. I learned not to get involved in those debates and conversations. I learned to just play tennis. That’s what I do best.”
Williams’ grand slam successes have so far spanned 17 years, her first coming at the US Open in 1999 and since then only five years have gone by when she has not added at least one to her collection.
As well as seven at Wimbledon, the 34-year-old now holds six singles titles at the Australian Open, three at the French Open and six at the US Open.
“There’s definitely some blurs between eight, nine and 10,” Williams said.
“I don’t even know where eight, nine and 10 were or when. I definitely don’t remember where 12 was.
“I remember one through four. It gets really blurry after that. I will definitely be able to place this one.”
Kerber was bidding to upset Williams for the second time in seven months, after stunning her prestigious opponent 161 days ago in the Australian Open final.
Many predicted that remarkable run would be a one-off but the world number four, who will rise to two on Monday, had been ruthless in these championships as she attempted to become the first German to triumph in SW19 since Graf, her friend and mentor, beat Arantxa Sanchez Vicario 20 years ago.
Williams, however, was more clinical this time around, her serve particularly potent as she conceded just one break point in the match, which she erased with a 117-miles-per-hour ace.
“Of course it feels disappointing, that’s for sure,” Kerber said.
“But also I know that I played a good final. I lost against a really strong Serena today. This makes a little bit better; I know that she won the match not that I lose the match. That makes it a little easier for me.”
There may also be some relief for Kerber’s coach Torben Beltz, who promised not to shave until his charge had lost at SW19.
“I think that’s his ritual. Tonight he will shave,” Kerber said. “After two weeks, he looks like crazy.”
Later on, the Williams’ sisters sixth Wimbledon success as a team came at the expense of Yaroslava Shvedova and Timea Babos, the American duo sealing a 6-3 6-4 victory.
Between beating Kerber in straight sets to take the singles title and being called to the court for the doubles, Serena had paraded her trophy, signed autographs, held a press conference and conducted television interviews.
But the 34-year-old and her 36-year-old sister showed little sign of distraction as they were comfortable winners against Kazakh player Shvedova and Hungarian Babos, Serena Williams putting away the match-winning backhand volley at the net.
A 14th women’s doubles title together moves the Williamses to a share of second place on the open era list, alongside the team of Gigi Fernandez and Natasha Zvereva but six adrift of the Martina Navratilova and Pam Shriver partnership.
The sisters won their first Wimbledon doubles title in 2000, which was also the year their dominance of the singles events began when Venus Williams defeated Lindsay Davenport in the final.
Serena Williams, turning to her sister, said: “I think you won in 2000, and we won doubles in 2000. Now it’s 2016 and we did the same thing.
“It’s unbelievable, it’s a feat even I couldn’t have thought would have happened. It’s amazing.”
That verdict was echoed by Venus, who lost in the singles semi-finals to Kerber but was thrilled to share in the doubles success.
With the Williams name on both champions’ boards again, it was another day to savour for the family.
“To have Williams on both of those once again, somehow, in 2016, it’s another dream come true,” Venus said.
And there may be more Wimbledon successes to come in the future, with neither sister giving any indication they are thinking of retirement.
“Who said that our age was old? Who put that stipulation on it?” said Serena. “Because it’s working for us.”