The Boston Celtics have been around for 76 seasons, made the NBA playoffs 56 times in their history, enjoyed the contributions of 48 Hall of Fame enshrinees, and retired 23 numbers — more than any other American sports team — that now hang from the rafters above the iconic parquet floors of TD Garden.

But none of those numbers are as significant as 17.

Dating back to the 1956-57 roster that featured Bill Russell, Bob Cousy, Tom Heinsohn, Frank Ramsey, and Bill Sharman while Red Auerbach called the shots from the sidelines, the C’s have earned a record-tying 17 titles in franchise history.

And while the 18th might be the sweetest of all because it would break the tie with the rival Los Angeles Lakers, those first 17 — and the seasons surrounding them — featured plenty of iconic moments, tragic developments, and unforgettable sequences that helped shape one of the richest histories the Association has seen.

In honor of those 17 championships, we’re highlighting the 17 signature moments, both good and bad, that took the Celtics from a woeful 22-38 BAA debut in 1946-47 to the current iteration of the longtime powerhouse franchise that’s now coming off an NBA Finals appearance.

17. Sam Jones’ last-second, off-balance shot swings momentum in the 1969 NBA Finals

A five-time All-Star who was eventually honored with a Hall of Fame induction and inclusion in the NBA’s 75th Anniversary Team, Sam Jones left plenty of indelible memories throughout the early portion of the Boston Celtics’ championship history. Perhaps none were more significant than the stunning game-winner that leveled the 1969 NBA Finals at two games apiece.

Jones himself might have exaggerated his intentions on that legendary shot, though.

16. Gerald Henderson crushed the spirit of the Lakers

The 1984 NBA Finals weren’t exactly going the right way for the Boston Celtics. Worse still, they were falling behind the hated Los Angeles Lakers. But with 18 seconds remaining in Game 2, Gerald Henderson added another entry to the list of legendary steals that have popped up at plenty of notable times throughout the Boston Celtics’ championship history.

This may be one of the most underrated moments in the franchise archives, but we’re not forgetting about it.

15. Isaiah Thomas took control with the heaviest of hearts

It’s tough to capture the hearts of a fan base more than Isaiah Thomas did in the immediate aftermath of his younger sister Chyna’s death. Not only did he suit up for the Boston Celtics during the 2017 NBA Playoffs, but he flat-out thrived with one of the best performances not just in his career, but in the storied history of the legendary franchise.

“I always dream of moments like this,” Thomas said after the unforgettable game. “Those are where legends are born. One day I want to be one of those guys.”

14. The tragic death of Reggie Lewis

Not every crucial moment in the Boston Celtics’ championship history is a positive one. The down periods are important, and one stretch of eight straight years without a winning record came directly after Reggie Lewis, a rising star in Beantown, collapsed on the court and died at 27 years old.

Lewis was the heir apparent to the long-tenured Big Three of Larry Bird, Kevin McHale, and Robert Parish, and his professional career was filled with promise. It just came to an end far too soon in what was an unabashed shock to the basketball world.

13. Bill Russell secures 8th straight title in Red Auerbach’s final game

What’s better than winning a title during your head coach’s final game in the NBA?

One possible answer: winning an eighth straight title and helping establish the Boston Celtics’ championship history during the earlier eras of the franchise’s lengthy tenure in the Association. Such was the case for superstar center Bill Russell, who helped take down the rival Los Angeles Lakers in a seven-game series to emerge victoriously from the 1966 NBA Finals.

12. Kevin McHale clotheslining Kurt Rambis is a momentum-changer

Can you even imagine the reaction if Kevin McHale’s infamous clotheslining of Kurt Rambis had taken place in 2022 instead of 1984?

Well, it didn’t. And the ’80s were a different time as the low-post artist received only a technical foul that would up providing an emotional lift en route to yet another title in the Celtics’ championship history. Momentum matters, after all.

11. John Havlicek’s high-profile steal saves the day

Havlicek stole the ball!

Johnny Most’s iconic call of John Havlicek’s inbounds steal is one of the most significant moments in the history of NBA broadcasting, but it falls short of the top 10 in our countdown. Still, considering the magnitude of the moments comprising the Boston Celtics’ championship history, checking in at No. 11 is nothing to sniff at.

10. Pair of offseason trades triggers worst-to-first season and 1st title in 22 years

Think today’s biggest NBA trades are impactful? Few can match the worst-to-first swing prompted by Danny Ainge’s pair of swaps prior to the 2007-08 season, which helped end a 22-year drought in the Boston Celtics’ championship history.

First came Ray Allen and Glen Davis in June. A month later, Kevin Garnett joined the fray.

The rest, as they say, was history.

9. The trade that set up an ’80s dynasty

Just imagine how NBA history might have been forever altered if Red Auerbach had actually used the No. 1 pick of the 1980 NBA Draft.

Instead, he sent it and the No. 13 selection to the Golden State Warriors for Robert Parish and the No. 3 pick that was soon used on Kevin McHale. As you might have heard, those two had quite the impact on the Celtics in the ’80s.

Joe Barry Carroll, who went to Golden State, with the top overall selection, had a slightly different career trajectory.

8. Larry Bird’s steal, assist stuns Pistons and swings Eastern Conference Finals momentum

Our biggest request is that you don’t forget about the assist.

Larry Bird’s steal in the waning seconds of Game 5 of the 1987 Eastern Conference Finals against the Detroit Pistons gets most of the attention, but his pass to a cutting Dennis Johnson should receive far more hype. In fact, we’re giving the totality of this sequence more love than the famed John Havlicek steal in 1965.

That Bird guy was pretty good, huh?

7. Double-OT thriller in Game 7 of 1957 Finals gives Boston first NBA title

Winning the first title in franchise history is pretty special, even when your number of championships eventually swells to 17. Earning it in Game 7 with a double-overtime victory over the then-St. Louis Hawks? Well, that’s even sweeter.

With 37 points and 23 rebounds, Tom Heinsohn was the star of the show in the title-clinching victory, but he was far from the only legendary name who featured in this memorable battle. Heinsohn himself even credited one of his teammates with “the most memorable play I’ve ever seen.”

6. Bill Russell’s massive double-double the difference in Game 7 of the 1962 NBA Finals

Thirty points and 40 rebounds in a single game?

That’s a stellar line no matter when it’s produced, but Bill Russell managed to put up those numbers in Game 7 of the 1962 NBA Finals. Against the Boston Celtics’ bitter rivals: the Los Angeles Lakers. To win yet another title in what seemed like an endless string of championships.

Yeah, that Russell guy was special.

5. ‘The Greatest Game Ever Played‘

Phoenix Suns. Boston Celtics. Gar Heard. Triple overtime. Championship No. 13.

Sometimes, you don’t even need complete sentences to properly advertise one of the most legendary battles in the history of basketball. That’s exactly the case for the Game 5 clash between the C’s and Suns on June 4, 1976, which resulted in a 128-126 victory for the men in green and has stood the test of time as a contest that continues to earn superlatives.

4. The Len Bias tragedy

Not every memorable moment for the Celtics has to be positive. The lows are crucially important to the history of this championship-compiling franchise, and no low was lower than the untimely death of Len Bias.

The Maryland product was supposed to be the next big superstar and take the reins from Larry Bird, ushering in the next dominant organizational iteration.

Unfortunately, that’s not even close to how it played out.

3. Drafting Larry Bird

If you really wanted to, you could call this moment … legendary.

The Boston Celtics’ championship history would’ve fallen flat during the 1980s if Red Auerbach hadn’t selected Larry Bird with the No. 6 overall pick of the 1978 NBA Draft. The rest was history — in the form of so many accolades and titles that Larry Legend will forever be considered one of the greatest players in league archives, all while only wearing a Celtics uniform.

2. Hiring Red Auerbach, a basketball pioneer

Usually, players take center stage. And while that’s largely true for the Boston Celtics, Red Auerbach was such an icon along the sidelines and when making personnel decisions that he can brush shoulders with even the best on-court contributors in franchise history.

Puffs of cigar smoke signaled countless victories. He contributed to the crowding of the rafters with championship banner after championship banner. So many Hall of Famers only wore Celtics green because he brought them to town.

Auerbach was the Celtics.

1. Bringing Bill Russell on board

The St. Louis Hawks could’ve had Bill Russell. Instead, the Boston Celtics wound up with one of the all-time greats, and he contributed more to the franchise’s championship history than anyone else.

Russell made 12 All-Star teams and 11 All-NBA squads. He won MVP five times and helped earn a staggering 11 championships behind his excellent defense and rebounding. Even beyond that, he was a pioneer off the court, irrefutably changing the sport for the better.

Acquiring him was, without question, vital to the Celtics.

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