Born on 16th April 1920 in Calcutta, died 18th September 1990. He studied the viola at the State Academy of Music in Stockholm, 1936-1941, and was taught counterpoint and composition there by Melcher Melchers. Further studies of composition followed in Denmark, the Netherlands, France, Switzerland and Italy. He entered the Catholic Church in 1950 (changing his name from Klas-Thure to Claude Loyola) and trained as a Catholic theologian.

Allgén had begun composing when he was only 16 years old, and in the mid-1940s belonged to the inner circle of the so-called Monday Group. Karl-Birger Blomdahl referred to him as “a hyperintellectualist who denies all vertical relationships or observes only negative rules (for example, that different parts are not allowed to meet on the same note) and mostly enjoys writing nine-part fugues with 100 per cent utilisation of his thematic material and practically unplayable tempi, and is a stickler for ‘single absolute objectivity’ (he just ‘starts up’ the music which then keeps going until it runs out)“.

Not infrequently, this objectivity resulted in a music which, due to its great length and technical difficulty, was considered unplayable. And indeed, most of his numerous compositions have never been performed. The list of works reported to the Swedish Performing Rights Society contains about 90 works, most of them piano and organ compositions, together with songs and choral compositions (quite often of a religious nature) and chamber music (his Sixth String Quartet, written in 1961, takes 50 minutes to perform, and a String Trio from 1975 lasts for one hour). But he also wrote orchestral works, including two symphonies (the orchestra required for the first of these includes twelve saxophones) and two other compositions lasting for over an hour each, viz. a Fantasy for Orchestra (1960) and a Violin Concerto written in 1957 (without any barlines).

His music is uncompromisingly consistent, dogmatic and complex .
Stig Jacobsson