Espen Mathiesen was born on May 10, 1995, in Egersund — a small coastal town on the west coast of Norway with a population of approximately 10,000 people. Long before he set foot on a BJJ mat, Mathiesen was a competitive footballer, beginning the sport at age 5 and playing until he was 16. Those years of structured competition, teamwork, and physical discipline quietly forged the dedicated grappler he would become.

At age 15, Mathiesen discovered Brazilian jiu-jitsu, beginning his training under Damoun Nassehi, a blue belt who had trained with Shimon Mochizuki at Checkmat/Arte Suave in Denmark. The exposure was immediate and transformative. Within seven months of stepping onto the mats, Mathiesen's commitment had already extended beyond the gym — he purchased mats and began drilling techniques daily at home alongside a friend, an early signal of the relentless self-motivation that would define his career.

Despite being on an academic track toward civil engineering, Mathiesen chose to take a gap year before university to dedicate himself fully to jiu-jitsu. That decision proved pivotal — rather than a brief detour, it became the launch point of a decorated competitive journey at the highest levels of the sport.

Building the Foundation

Mathiesen's connection to José Carlos of Kimura - Nova Uniao began in 2011, when José Carlos visited Damoun Nassehi's gym in Norway to conduct a seminar. That encounter initiated a coaching relationship that would carry Mathiesen all the way to black belt. In the years that followed, Mathiesen relocated to Haugesund, Norway, to access a more professional and structured training environment — a move that reflected both his ambitions and his willingness to sacrifice comfort for competitive growth.

Colored Belt Dominance

His progression through the colored belt ranks was rapid and decorated. A silver medal at the IBJJF World Championship in 2015 at purple belt announced his arrival as one of Europe's most promising talents in the Peso Leve division. As he advanced to brown belt, that promise was fulfilled emphatically: in 2017, Mathiesen claimed gold at both the IBJJF European Open and the IBJJF Pan Championship, establishing himself as the dominant force at his level before reaching the sport's top competitive tier.

Black Belt Promotion and Early Results

In July 2017, José Carlos promoted Mathiesen to black belt, bringing to a close one of the most accomplished colored belt careers in recent Norwegian BJJ history. The promotion did not signal a slowdown — it opened a new chapter of sustained elite performance. Mathiesen earned a bronze medal at the 2018 IBJJF World Championship, confirming his ability to compete with the world's best at the sport's most prestigious event. His gold medal at the 2022 IBJJF European Open Championship demonstrated the durability of his skills and his continued relevance at the highest levels of competition well into his black belt career.

Multi-Format Versatility

Across his black belt career, Espen Mathiesen has built a record that spans the major international competitive formats, cementing his place among Europe's elite in the Peso Leve division (76 kg / 168 lbs). His performances span both the IBJJF circuit and submission-oriented grappling events, underscoring a versatility that few competitors at his level can match.

In 2017, Mathiesen finished as runner-up at the Copa Pódio 76KG Grand Prix, one of the most prestigious invitation-only formats in the sport. Competing against elite international opposition in that setting confirmed that his decorated brown belt campaign was no fluke. That same year, he also claimed gold at the 2017 IBJJF Copenhagen Open, further demonstrating his consistency across multiple competitions within a single season.

International Circuit Achievements

In 2018, Mathiesen added an AJP Abu Dhabi World Pro title to his résumé, showcasing his adaptability across different rulesets and competitive formats beyond the IBJJF. He returned to the AJP Abu Dhabi World Pro podium in 2021 with a silver medal, reflecting his sustained commitment to competing internationally across multiple years of his black belt career. His 2022 IBJJF European Open Championship gold rounds out a body of work that speaks to both his competitive longevity and the breadth of his accomplishments.

Mathiesen has also taken on leadership responsibilities within the competitive arena, leading the Kimura - Nova Uniao team at Copa Pódio's Kids Challenge — a role that placed him at the intersection of his identity as a competitor and as a representative of his organization.

An Early Start on the Teaching Side

One of the most distinctive threads running through Espen Mathiesen's story is that his coaching career did not begin after his competitive career — it began alongside it. Mathiesen started teaching BJJ classes as early as his white belt days, an unusually early start that reflects both a natural aptitude for instruction and a genuine enthusiasm for sharing the art. That inclination toward coaching has remained a consistent part of his identity throughout his development as an athlete.

Mathiesen treats coaching not as an obligation or secondary pursuit, but as a meaningful parallel to his work as a competitor. That dual commitment sets him apart within European BJJ, where many athletes delay or deprioritize teaching until their competitive careers wind down.

Leadership and Community Investment

His leadership of the Kimura - Nova Uniao contingent at Copa Pódio's Kids Challenge was a visible expression of that identity — Mathiesen as not just an individual competitor, but as a team leader invested in the development of younger athletes. He has publicly acknowledged the support of Kimura - Nova Uniao, Moka Hardware, and Copa Podio in providing the infrastructure and opportunities that have shaped his career.

Within the Norwegian and broader European BJJ community, Mathiesen occupies a well-rounded role: a black belt under José Carlos whose career has been defined by competitive achievement, an early investment in coaching, and a long-standing commitment to the growth of the sport in his home country.