Matthias, also known as Matthias the Apostle, was chosen to replace Judas Iscariot as one of the Twelve Apostles, according to the Acts of the Apostles. He was selected by the apostles through prayer and casting of lots. Not much is known about Matthias from the canonical New Testament, and even his name varies in different sources. There are conflicting accounts of his ministry and death, with traditions claiming he preached in various regions and met different fates, including crucifixion, stoning, and beheading. There are surviving fragments of a lost Gospel of Matthias attributed to him, but Early Church Fathers considered it heretical. Saint Matthias is venerated in various Christian traditions, with his feast day celebrated on different dates, including 14 May in the Roman Catholic Church and 9 August in the Eastern Orthodox Church. He is remembered for his unique calling as an apostle and his contribution to the early Christian community.

Matthias Steiner, born on August 25, 1982, is a retired Austrian-German weightlifter and Olympic gold medalist. He initially competed for Austria, winning four Austrian National Championships and setting records in weightlifting categories. In 2005, Steiner moved to Germany after marrying a German woman, and eventually received German citizenship. Despite the tragic loss of his first wife in a car accident, Steiner continued his weightlifting career and achieved great success. He suffers from Type-1 diabetes, diagnosed at the age of 18. Steiner's weightlifting career spans several championships and competitions, including the 2008 European Championships and the 2008 Summer Olympics, where he won the gold medal. His perseverance and resilience have made him an inspirational figure in the world of weightlifting.

Matthias Jakob Schleiden (1804-1881) was a German botanist, renowned for co-founding cell theory with Theodor Schwann and Rudolf Virchow. He developed a passion for botany and plant embryology, ultimately becoming a professor of botany at the University of Jena. Schleiden's pivotal work, "Contributions to our Knowledge of Phytogenesis," emphasized that all plants are composed of cells, and recognized the significance of the cell nucleus and its connection with cell division. His collaboration with Schwann led to the formulation of the theory that all living organisms are comprised of cells, a principle of biology equal in importance to the atomic theory of chemistry. Additionally, Schleiden was noted for his advocacy of Judaism, and his defense against antisemitism. He was an early advocate of evolution and played a crucial role in popularizing science in Germany through his accessible writings. Schleiden's contributions to the field of botany and his important role in the formulation of cell theory have left a lasting impact on the scientific community.

Matthias Josef Maurer is a renowned German astronaut and materials scientist who was chosen in 2015 to undergo space training. He has an impressive educational background, having graduated from various prestigious institutions across Europe and holding a doctorate in materials sciences. Additionally, Maurer holds several patents in the field of materials science and engineering, showcasing his expertise and contribution to the scientific community. Fluent in multiple languages, including German, English, Spanish, and French, Maurer has also taken intensive language training in Russian and Chinese as part of his astronaut preparation.Maurer's journey to becoming an astronaut began when he applied to the European Space Agency in 2008 and was selected out of almost 8500 candidates. Over the years, he has been involved in various space-related projects and training programs, demonstrating his dedication and commitment to space exploration. In 2021, Maurer was part of the SpaceX Crew-3 mission, where he traveled to the International Space Station alongside other astronauts. His notable contributions during the mission included performing maintenance tasks outside the station, highlighting his hands-on experience and expertise in space operations. With his exceptional skills and determination, Matthias Josef Maurer continues to inspire and contribute to the advancement of space exploration and scientific research.

Matthias Foss Cowley (August 25, 1858 – June 16, 1940) served as a member of the Quorum of the Twelve Apostles of the Church of Jesus Christ of Latter-day Saints (LDS Church) from 1897 to 1905. Cowley's tenure came to an end due to his refusal to support the church's decision to discontinue plural marriage. This led to his resignation from the Quorum of the Twelve, a rare occurrence in the history of the LDS Church. Despite his significant contributions and influence through sermons on doctrine, his actions led to his departure from the Quorum. Following his resignation, reports of his involvement in new plural marriages led to his priesthood being suspended by the church in 1911. This suspension lasted for nearly 25 years before his priesthood standing was finally restored in 1936, although he was never reinstated to his position in the Quorum of the Twelve. Cowley's legacy extends beyond his religious role, as the town of Cowley, Wyoming, is named in his honor. He was also the father of LDS Church apostle Matthew Cowley and FBI agent Samuel P. Cowley, known for his death at the hands of notorious criminal Lester "Baby Face Nelson" Gillis in 1934. Cowley's published works continue to provide insight into the history and teachings of the LDS Church.