At the age of 20, Matania began working in Paris for Illustration Francaise and, in 1902, was invited to London to cover the Coronation of Edward VII for The Graphic. Matania would subsequently cover every major event – marriage, christening, funeral and Coronation – of British royalty up to the coronation of Queen Elizabeth in 1953.
In 1904, Matania joined the staff of The Sphere where some of his most famous work was to appear, including his illustrations of the sinking of the Titanic in 1912. At the outbreak of the First World War, Matania became a war artist and was acclaimed for his graphic and realistic images of trench warfare.
Matania exhibited regularly at the Royal Academy and Royal Institute from 1908 and his work appearing in most of the principal magazines in Britain and America, including Illustrated London News, London Magazine, Nash's, Printer's Pie and others. When Britannia and Eve was launched in 1929, Matania became one of its first contributors. For 19 years, he wrote and illustrated historical stories for the magazine. His talents made him a popular illustrator for advertising, posters and catalogues, working for Ovaltine, Burberry's (the sporting outfitters) and many others. Matania was also recommented to Hollywood director Cecil B. DeMille and produced a number of paintings of Rome and Egypt from which authentic designs could be made for the movie The Ten Commandments.
Towards the end of his life, Matania illustrated features for the educational weekly Look and Learn and was working on the series A Pageant of Kings at the time of his death.