Maryland-Native Isabelle Bosley Scores A Wire-To-Wire Finish In MARS Maryland 5 Star CCI3*-L

Bosley and Conner Pony Up For A Win In The MARS Maryland 5 Star CCI3*-L

By Mollie Bailey

— first published in the November 2025 issue of The Equiery

As Isabelle Bosley led the victory gallop for the MARS Maryland 5 Star CCI3*-L, she had an awful lot of supporters cheering for her. There were her family and a tight-knit group of supporters who attend many of her events as well as loads of old friends who came to Elkton to watch the Monkton, Maryland-native score the biggest win of her career aboard Karen Martin’s Conner.

“As I was galloping I started hearing really loud shouts, and I would kind of look up and see a face I know, and then I’d hear another really loud shout, and I look up and see a whole other group of people cheering for me,” said Bosley, 28. “It made me really emotional because I just didn’t realize how many people had come out to support me. To kind of see and hear all the faces that were there out there was really special.”

Bosley, who now lives in Unionville, Pennsylvania, and Conner set the standard with a dressage test that she said felt better than any they’d done before to take the lead early in the competition. Then, the two put in a foot-perfect cross-country round and a flawless show jumping trip to earn the win.

Bosley’s partnership with Conner has roots at Fair Hill. Back in 2022, Bosley was grooming for another Maryland-native, Lillian Heard Wood, at this event when she started chatting with Kara Angulo. Bosley was on the lookout for a special young horse, and Angulo had a knack for finding them. Angulo had a 5-year-old in mind she was thinking of importing from Germany, but she wasn’t sure yet, so Bosley said to call if he came over. When he landed in the United States a month later, Bosley dropped everything to try him, immediately falling in love with his precocious sense of balance and the feeling he gave her over the jumps.

Bosley took things slow with the talented but quirky Oldenburg (Casiro 3 x Concetto), building up his strength and proceeding step by step to keep him confident. He didn’t attend his first competition until the summer of his 6-year-old year, stepping him up to preliminary the next season where he started to shine. This season, she intended to wait until later in the year to step up to intermediate, but at coach Phillip Dutton’s suggestion, she gave it a try in March at the Ocala Winter II Horse Trials where she won the competition. She’s won three other national-level horse trials this year, as well as the Maryland International CCI3*-S, and placed second at two more Fédération Equestre Internationale events.

“He’s been so much fun to bring along,” she said. “He’s actually a really sensitive little baby boy and acts like a foal in the barn. He just wants to be cuddled and just loves humans. He’s the biggest smush of a horse, and he’s everyone’s favorite.”

Bosley grew up immersed in the horse world, thanks to her parents Louis and Tricia Bosley, who trained racehorses. Isabelle rode her pony out on racehorse sets and foxhunted, despite her parents’ insistence that she do other things besides just horses. She started out in the show hunter ring but quickly swapped to eventing.

“I was 6 or 7 at my first event at Full Moon Farm,” recalled Isabelle. “I got like a 50 on the flat, fell off at the first show jumping and had multiple refusals cross-country. I finished the day crying, but I loved it. And I think I got humbled very quickly in the sport. I was like, ‘OK I love eventing.’ ”

Isabelle galloped racehorses and rode in steeplechases a bit (“I thought I wanted to be a jockey,” she said) but she always came back to eventing. She started working with Wood when she was 16 and stayed there for nearly a decade. Isabelle trained a few Thoroughbreds she’d hoped would take her to the top of the sport, selling them when they turned out to be more limited than she’d hoped.

“I remember turning 21, and I’d never gone past training [level],” said Isabelle. “I had no good horse and there was a serious moment where I was like ‘Do I quit? Where am I going with this? This isn’t going anywhere.’ ”

That’s when she met Night Quality. That Irish Sport Horse took her to the advanced level and to her first FEI competitions, and they represented Team USA in a Nations Cup competition in England in 2022. She earned the inaugural Annie Goodwin Rising Star Grant at the end of the next year.

“After [Night Quality] told me that the four-star level was a little too hard for him, I felt a little displaced,” she said. “You get that taste of the top level and then when you don’t have it, it’s hard. I felt like I was taking steps back, but then all of a sudden you start to get yourself back there.”

A big part of getting back there has been thanks to her relationship with Karen Martin, who owns Conner and her homebred three-star horse, Paper Doll, for Isabelle. She’s owned horses for Isabelle for about seven years. Martin wasn’t in Elkton for the Maryland 5 Star, but when Isabelle called her immediately following her ride, she was ecstatic at the accomplishment, the culmination of hard work by Conner and Isabelle over the last three years.

“I kind of try to remind myself to look back where I was five years ago, where I was 10 years ago,” said Isabelle. “Then I say ‘OK, things are going in the right direction.’

“It’s so exciting to do this at Fair Hill,” she added. “I remember as a kid going to the big three-day in the fall there, thinking ‘God I just want to do this one day.’ So it’s been really surreal when I stop and think, ‘You’re doing this now. This is really cool.’ ”