He made significant contributions to lichenology, particularly through his work Lichenographia scandinavica (1871–1874), and introduced innovative research methods including the systematic use of microscopy in botanical studies.

Fries participated in two Arctic expeditions led by Adolf Erik Nordenskiöld, traveling to Bear Island and Spitsbergen in 1868 and to Greenland in 1871.

His time at the school was marked by an unwavering commitment to education, leading him to graduate as the top student in 1851, a testament to his intellectual capabilities and the strong foundation laid during his early years.

At seventeen, he published his first work, documenting a botanical excursion in Uppland, where he observed Najas flexilis in Lake Hedersvik and described aegagropila algae formations.

[2] Theodore "Thore" Magnus Fries began his academic and research career after graduating from Uppsala Cathedral School, where his early publications reflected a budding interest in botany.

[2] Fries held several early academic positions, including amanuensis at the botanical garden and museum (1853–1859) and docent in botany at Uppsala University from December 1857.

[2] Fries balanced his academic career with teaching roles, including natural history instruction at Uppsala Lyceum (1856–1860) and a position at the Ultuna Agricultural Institute (1863–1867), where he later joined the board of directors (1878–1889).

[7] In January 1862, Fries faced a major professional challenge due to a conflict with Johann Emanuel Zetterstedt and William Nylander, rooted in longstanding academic rivalries and differing scientific viewpoints.

He carefully documented intraspecific variations, producing specimens of exceptional quality that formed the foundation of Uppsala's renowned lichen collection.

[7] Fries's scientific expeditions, including journeys to polar regions, greatly advanced his research in lichenology and phanerogams (seed plants).

[7] His tenure as Borgströmian professor of botany and practical economy, beginning in 1877, and his role as rector of Uppsala University demonstrate his impact on botanical science and education.

Drawing on his observations, Fries published "Greenland, its nature and inhabitants" in 1872, providing an in-depth account of the island's environment and culture.

[2] Fries made significant contributions to lichenology, historical botany, and the study of Linnaeus, including major works like Lichenographia Scandinavica.

[2] Fries's research style was characterised by exceptional attention to detail and thorough documentation practices that proved valuable long after his time.

For example, his detailed observations of unusual iodine reactions in hymenia and the presence of distinct types of paraphyses in certain species remained the most complete accounts of these features well into the modern era.

The specimens he preserved in Uppsala's lichen herbarium are noted for their careful preparation and thorough documentation, making them valuable reference materials for contemporary researchers.

His lichenological courses were groundbreaking for their time, combining theoretical lectures with extensive hands-on practical exercises that allowed students to study lichen structure both macroscopically and microscopically.

[7] Furthermore, Fries's commitment to education was demonstrated through his leadership and involvement in the Botanical section of the Natural Science Students' Society, which he founded and sustained for over fifty years.

He was known to start each academic term with practical demonstrations in the botanical garden, ensuring students not only learned about plant life theoretically but could also recognise and understand it in a real-world context.

This hands-on approach, combined with his dynamic teaching style, left a lasting impact on generations of botanists, making his courses memorable and establishing a rich educational legacy.

Born on 6 November 1844, in Österby bruk, Film parish, she was the daughter of Claes Abraham Anjou, a master hammersmith, and Anna Maria Öhrn.

In 1903, Fries was awarded the great cross of the Order of the Polar Star, a prestigious Swedish honour recognising his contributions to science and education.

Completed in his later years, this work underscored Fries's role as a link between historical and contemporary botanical exploration, enriching the understanding of Linnaeus's legacy.

His funeral on 3 April 1913 at Uppsala Cathedral was attended by family, friends, colleagues, and students, demonstrating the broad impact of his life and work.