Born in Pigeon Hollow, West Virginia, as Pete Cooney, he wooed Lottie Chandler, fathered her son Ross, and abandoned her. He changed his name to Palmer Cortlandt and made a success of himself. Palmer fell in love with Daisy, the housekeeper's daughter. They had a child together, Nina, and for years, Palmer had his daughter believing that her mother had died, while she was in fact very much alive. He had kicked her out when he had discovered that she was having an affair. Being the overprotective father that he was, he tried to ruin his daughter's relationship with Dr. Cliff Warner in many diabolical ways. First, by enlisting the help of nurse, Sybil Thorne, who seduced Cliff and became pregnant with their son Bobby. Next, he tried to convince diabetic Nina that she was going blind due to her illness and shouldn't burden Cliff with an invalid wife. Then he hired sexy Steve Jacobi to work with and seduce Nina at Cortlandt Electronics. Eventually true love won out (after four marital attempts) and the happy Warner's left Pine Valley together.
Shortly after arriving in Pine Valley, Palmer became interested in and married ex-hooker Donna Beck, thinking that he could make her into the worldly woman that he longed to have on his arm. While enjoying a skiing trip to Switzerland Palmer and Donna ran into her ex-husband, Chuck Tyler and his new girlfriend, Melanie. As they were all skiing together an avalanche surprised them and Chuck and Donna found themselves trapped in a cave. Convinced that they would never be rescued, they made love. They were rescued, nevertheless, the next day, and upon returning to Pine Valley Donna discovered that she was pregnant. She was thrilled but Palmer was suspicious because he was sterile due to a polo accident years earlier. Not wanting to arouse suspicions, Palmer played out the role of doting husband and father. Soon however, the truth came out and it was revealed that the baby was indeed Chuck's and Palmer and Donna separated.
After an unsuccessful second try with Nina's mother, Daisy, Palmer became interested in his son Ross's ex-wife, Cynthia Preston. Cynthia came to town looking for a meal ticket and dug her claws deep into Palmer. He was thrilled with the attention of this attractive young brunette and genuinely developed a bond to her teen-age son, Andrew, who Palmer envisioned as the heir to Cortlandt Electronics. However Cynthia fell into an affair with Ross and thus out of Palmer's good graces, and Andrew was sent to jail for participating in the death of Alexander Hunter.
When Palmer was shot by a thug hired by Adam Chandler, he hired nurse Natalie Marlowe to look after him. Palmer and Natalie fell in love and planned to marry, but Palmer's son Ross also had eyes for Natalie. Soon they were having a steamy affair and worried to death that Palmer would find out. As the pressure came down on him, Ross raped Natalie who was thrown out by Palmer. However Palmer's feelings for Natalie lingered, and he wasn't yet willing to let her go. When Natalie was attacked by Silver Kane and accidentally shot her, Palmer hid the body in a pond on his property and blackmailed Natalie into reconciling with him. Next, when Natalie started a relationship with her lifelong heartthrob Jeremy Hunter, Palmer brought his ex-lover Marisa Rampal to town to break them up.
Never being quite satisfied with his family members´ choices in the love department, Palmer set out to destroy his naive niece Dixie's happiness with Tad Martin. Palmer paid Tad's mother Opal to help him break them up, and they succeeded. But Palmer had not planned on falling in love with his partner in crime in the process and with his ex-wife Daisy playing matchmaker, "PC" and Opal married in November 1990. On Christmas Day 1992, Opal and Palmer welcomed the birth of their son, Peter.
Government agent Mike Roy and partner, Adrian Sword, arrived in town to find stolen Nazi paintings. Palmer, after much Palmer-like posturing, possessed the paintings and plea-bargained his way out of charges. The definitive end to Palmer and Opal's marriage came when Palmer had to decide between relinquishing the paintings and staying with Opal or faking his death and escaping with the artwork. In the end he lost both. Irritated with Opal's friendship with Adrian and her aid in catching him, Palmer sought revenge on Opal and made her reveal that Adrian was her son from an interracial affair. This blew Adrian's FBI cover and his mind. Adrian forced Palmer into signing a divorce decree that was very generous to Opal.
Palmer became taken by Pine Valley debutante, Vanessa Bennett. They were married at sea while on vacation. Palmer admitted to Erica that he didn't really love Vanessa, but said that having an attractive woman on his arm is never a bad thing. Shortly after their marriage, Vanessa was almost divorced by Palmer when he found out that she was borrowing oodles of money to help a much younger man. Palmer believed that this young man, Leo, was Vanessa's lover. He had Leo kidnapped and set-up a plot that would make it look like Leo had killed Vanessa in a jealous rage. When it came time for the shooting, Vanessa revealed that Leo was her son --- not her lover. Palmer jumped in front of Vanessa and took the bullet. Vanessa learned that Palmer had plotted to kill her and used the shooting as leverage for months.
Vanessa's parenting skills came under fire when she reverted to her old, adulterous ways. Vanessa found her way into the bed of a young, shady character named Paolo Caselli. The two were not strangers; they'd apparently had an affair several years prior in Europe. Things got complicated when Paolo threatened to expose Vanessa's affair to Palmer. Leo was roped in when he hired Paolo to seduce Marian Chandler on Adam's request; the hope was that Stuart would ditch Marian if she had an affair with Paolo. Paolo ended up dead - and Leo was arrested because he was found hovering over Paolo's dead body. It turned out that Vanessa had accidentally killed Paolo by slipping too much of a powerful sedative into his wine. That and a high level of cocaine already in Paolo's system did him in. Vanessa never spoke up to defend her son because she feared that it would mean the end of her free ride with Palmer. Vanessa was set-up, thanks to some help from David, to confess the truth --- David slipped her a medication that made her think she was having a heart attack. The charges against Leo were subsequently dropped after Palmer hired someone to "lose" the evidence in the case, though no one ever spoke publicly of what Vanessa had done. Palmer used Vanessa's involvement against her, just as she had used his murder plot against him.
Palmer and Vanessa once again became cozy when Palmer learned that Vanessa had been blackmailing Arlene Vaughan Chandler over her involvement in nearly killing Stuart Chandler. Palmer loved it because Arlene's money was Adam's money --- and Palmer loved sticking it to Adam. After Vanessa confessed to another affair -- with her chauffeur, Larry -- Palmer kicked her out of their room at The Valley Inn and sought a divorce.
Palmer's attention then turned back to Opal. When he discovered that Opal had a new admirer, musician Hank Pelham, he was jealous of this new relationship. Using his influence, Palmer got Hank a job touring with a band, thus eliminating the competition since Hank had to leave Pine Valley.
Palmer was happy to see his grandson Bobby back in town until he realized that Bobby had never really grown up. Bobby bilked money out of Edmund Grey before leaving town, without a goodbye to Palmer. A few months later, he was shocked when newcomer Diana Cole claimed to be his supposedly deceased niece Dixie. He believed what she was saying, and was devastated when it turned out that she was lying. It was much harder for him to accept when the real Dixie turned up alive and well.
Palmer relocated to Switzerland in August of 2008 and in March of 2009, it was revealed Palmer invested with someone who swindled him out of all of his money, leaving him, Pete, and Opal broke. Palmer was unable to be reached when Opal tried to contact him regarding what had happened to their money. Palmer quietly returned to Pine Valley in April of 2010 and he planned to surprise Opal. Before he had a chance to see her, he suffered a heart attack and died in his hotel room.
Jackson Montgomery notified Palmer's family and friends that he did not want a formal memorial service held. Instead, an informal gathering was held at Tad Martin's home and fried chicken was served to commemorate Palmer's time working at the Chicken Shack and a reminder how he had turned the fast-food restaurant into a million dollar business. Daisy and Nina returned to Pine Valley and joined the others in reminiscing their time with Palmer. After the memorial ended, everyone went home and lit a candle at midnight and said a private farewell to Palmer. He was welcomed into the white light by a vision of Dixie.