Born in London in 1902, Brill spent part of his early childhood in Yorkshire returning to London during the First World War. At the age of 13, he was living in lodgings in London, working in a City office and self-funding evening classes at St Martins School of Art. There followed a scholarship to The Slade in 1921, where he studied under Henry Tonks, whose teachings are evident in Brill’s monumental figures.
In 1927 he won the Prix de Rome for Decorative Painting and subsequently spent two years at The British School in Rome. Brill then went on to teach at Blackheath School of Art before spending three months painting in Egypt.
Like so many artists born in the early 20th Century, Reginald Brill found it difficult to make ends meet from painting, so he decided to pursue teaching as an alternative source of income. He applied for the job of Head Teacher at Kingston School of Art and took up the post in January 1934. Brill found it bohemian and chaotic, so he proceeded to inject enthusiasm, order and discipline. Within five years a £100,000 purpose-built School of Art was opened in Knights Park. Under his skilled and totally dedicated direction Kingston established a national reputation for excellence.
Brill gained huge respect and admiration from the hundreds of pupils who studied under his 30-year leadership.
He published two books, Modern Painting 1946 and Art as a Career 1962, both bearing a strong educational angle. He regularly exhibited along with leading artists of his era at The Royal Academy, in all some 45 paintings and acutely observed drawings. His perfectionism, astute powers of observation and relentless research can be seen in his paintings which reflect mid-20th century British Art at its most typical. Like Stanley Spencer and William Roberts, he devoted much of his time pursuing a constant theme. His major series of work, known as 'The Martyrdom of Man', was produced in parallel to his career as a teacher. These paintings reflect his care for fellow man and sensitively depict people at work, e.g. Linemen, Waiting Room, Rest, and most notably Rural Roadworks.
Brill retired from Kingston School of Art in 1962 and lived out his remaining years at Little Hall, Lavenham, Suffolk.