Affirmed was a chestnut horse bred in Florida by Louis E. Wolfson’s Harbor View Farm. The derivation of the name “Affirmed” has been the subject of speculation, in part because the conviction of Wolfson, for securities law violations had been affirmed on appeal in 1969 resulting in his imprisonment. He was sired by the Harbor View stallion Exclusive Native, a high-class racehorse and breeding stallion, whose other progeny included the Kentucky Derby winning filly Genuine Risk.  As a two-year-old, Affirmed won seven of his nine starts with two placings for earnings of $343,477 under regular rider Steve Cauthen, then a teenager. Notably, six of those starts were against his rival, Calumet Farm’s Alydar, with Affirmed winning four and Alydar winning two.  With his 4-2 margin in the series, Affirmed was named the 1977 American Champion Two-Year-Old Colt.

Alydar was made the 6-5 favorite for Kentucky Derby, with Affirmed the second choice at 9-5. Undefeated, Sensitive Prince was the third favorite at 9-2. At the start of the Kentucky Derby, Sensitive Prince took the early lead as Affirmed ran in third through the early stages, while Alydar stayed far back. Affirmed made a strong move for the lead on the far turn, put away a challenge by Wood Memorial winner Believe It, and held off Alydar’s fast-closing charge to win by 1½ lengths. Affirmed now had a 5-2 edge in the series.  In the Preakness Stakes, Affirmed set the pace. Alydar made his big move on the far turn, at the same point in the race where Affirmed made his winning move in the Derby. Affirmed held a short lead entering the stretch and held it to defeat Alydar by a neck.

Alydar’s partisans assumed that the 1½ mile distance of the Belmont, two furlongs longer than the Derby and 5/16 of a mile longer than the Preakness Stakes, would favor Alydar with his finishing style and staying pedigree, and he would deny Affirmed the Triple Crown. Trainer Veitch removed Alydar’s blinkers for the Belmont, saying that if Alydar got a better look at Affirmed, maybe he would get by him.

In the Belmont, Affirmed led and set a very slow pace, going the first quarter mile in 25 seconds and the half in 50 seconds. Alydar’s jockey, Jorge Velasquez, put Alydar close to the pace, and moved alongside Affirmed with more than seven furlongs to go. For more than six furlongs, the colts raced neck and neck, pulling away from the rest of the field. Alydar got his nose in front at mid-stretch, but just as Affirmed appeared to tire, Cauthen went to a left-handed whip, something he had never done before in his eight rides on Affirmed. Affirmed won by a nose to become racing’s 11th (and as of 2014, the last) Triple Crown winner. After the third slowest start in Belmont Stakes history, they raced the fastest last mile in Belmont Stakes history, 3/4 in 1:14, the mile in 1:37 2/5 and finished in 2:26 4/5. It was, at the time, the third fastest Belmont ever, behind Secretariat and Gallant Man.

Affirmed returned to racing in early August in the Jim Dandy Stakes at Saratoga. He nearly became an upset loser to the front-running Sensitive Prince but closed in the last 100 yards in a race that Laz Barrera considered one of Affirmed’s finest efforts.  Alydar and Affirmed met once more, in the Travers Stakes at Saratoga. Affirmed, piloted by Hall of Fame jockey Laffit Pincay substituting for the injured Cauthen, cut off Alydar entering the far turn, causing his rival to check suddenly. Affirmed finished first but was disqualified and placed second. The horses never met again, and the final winning tally stood at Affirmed 7, Alydar 3.

Affirmed then prepared to meet another major rival: 1977 Triple Crown winner Seattle Slew. The 1978 Marlboro Cup Invitational Handicap marked the first time in racing history that two Triple Crown winners ever met in a race. Seattle Slew was a speed horse and got the first quarter mile in 24 seconds under jockey Angel Cordero, who never allowed Affirmed to get close. Seattle Slew won by three lengths in 1:45 4/5 for the one-turn mile and 1/8. The two horses met once more, in the Jockey Club Gold Cup. This time, Affirmed was to be aided by his stablemate Life’s Hope, who was entered in the race to extend Seattle Slew in the early stages. However, Affirmed’s saddle slipped during the race, leaving his jockey with almost no control. He tired to finish unplaced as Exceller and jockey Willie Shoemaker defeated Seattle Slew by a nose.  As a three-year-old, Affirmed won 8 of 11 starts with 2 seconds and 1 unplaced run, for earnings of $901,541. He was named Horse of the Year despite the losses to Alydar, Seattle Slew, and Exceller, and was also named the American Champion Three-Year-Old Male Horse.

As a four-year-old in 1979, Affirmed started the season with a third place in the Malibu Stakes and a second in the San Fernando Stakes. He had a five race losing sequence prior to starting in the Charles H. Strub Stakes at Santa Anita Park. Laz Barrera replaced Cauthen with Pincay and Affirmed didn’t lose again and would dominate the handicaps the rest of the year.

Affirmed won the Strub Stakes, and then ran in the Santa Anita Handicap against Exceller, who had defeated Seattle Slew in 1978. Affirmed won easily, setting the stakes record in California’s most important stakes race which still stands as of 2008. Affirmed then went to Hollywood Park, where he won the Californian Stakes, carrying 132 pounds, he then won the Hollywood Gold Cup in a three horse finish, from Sirlad and Text, setting an all time earnings record and running the 1¼ miles in a fast 1:58 2/5. Affirmed picked up the Woodward Stakes at Belmont Park, and then faced one more all time great horse, three-year-old Spectacular Bid, in the Jockey Club Gold Cup, also at Belmont. Spectacular Bid, like Alydar, preferred to run off the pace, and once again, Affirmed was allowed to set a slow pace, going the first half mile in 49 seconds. Spectacular Bid issued challenges at Affirmed, but Affirmed won. Spectacular Bid was undefeated during the rest of his racing career.

Affirmed was named Horse of the Year and the American Champion Older Male Horse of 1979, having won 7 of 9 starts with 1 second and 1 third as a four-year-old and earning $1,148,800. In his career, Affirmed earned a then record $2,393,818 (the first Thoroughbred in North America to win over $2 million) with 22 wins, 5 seconds and 1 third from 29 starts.  His trainer, Laz Barrera, once said: “Affirmed is greater than Secretariat, or any Triple Crown winner, because only Affirmed had to face Alydar.”

Affirmed was syndicated at a then-record 14.4 million dollars. At stud Affirmed sired over 80 stakes winners, 9 champions with earnings in excess of $44,000,000 (through 2004) including:

Charlie Barley (USA), stakes winner in US
Flawlessly, North America’s grass course champion in 1992 and 1993
Peteski (CAN), won USA Molson Export Million Stakes and Canadian Triple Crown.
The Tin Man, won multiple Grade I races, including the Arlington Million
Trusted Partner (USA), won G1 IRE One Thousand Guineas
Though Affirmed never raced on the turf (grass) he was a noted sire of turf runners, most notably multiple Grade I winners Flawlessly and The Tin Man. His daughters are valued as broodmares.

In 2001, Affirmed was euthanized after falling seriously ill with laminitis, a circulatory hoof disease. The same disease has also led to the death of fellow Triple Crown winner Secretariat and Kentucky Derby winner Barbaro. He was buried whole—the ultimate honor for a race horse—at Jonabell Farm, wearing the flamingo pink colors of his original owners, Harbor View Farm.

In the Blood-Horse magazine ranking of the top 100 U.S. thoroughbred champions of the 20th Century, Affirmed was ranked #12.  Affirmed’s Triple Crown accomplishment has not been repeated since, and his career has been honored with his election to the National Museum of Racing and Hall of Fame.