The first clear evidence of a division of the Psalter for use in the
Western Church is found in the work of St. Benedict (480-543). He had
spent his youth near Rome, and keeping his eye on the Roman usage he
assigned the Psalms to the various canonical hours and to different days
of the week. The antiphons he drew from existing sources, and of course
the canonical hours were already in existence. In his arrangement, the
whole Psalter was read weekly, and the whole Bible, with suitable
patristic selections, was read every year. He also arranged the Sunday,
Festal and Ferial offices. For the recitation of the offices of a
saint's day, St. Benedict arranged that the Matins shall have the same
form as a Sunday office--_i.e._, three nocturns, twelve lessons and
responsories, but the psalms, antiphons and lessons are proper to each
saint. This arrangement interrupted the weekly recitation of the whole
psalter, and caused great difficulty in later times; for when the feasts
increased in number the ferial psalter fell almost into complete disuse.

St. Benedict's arrangement of the psalms and his other liturgical
regulations spread rapidly, but the Roman secular office never adopted
his arrangement of the psalms, nor his inclusion of hymns, until about
the year 1145. In some details each office shows its independent
history. It is a matter of dispute among liturgists whether Prime and
Compline were added to the Roman secular office through the influence of
the Benedictines (Baudot, _The Roman Breviary_, pp. 19-26).

The period following the death of St. Benedict in 543 is a period of
which little is known. "We repeat with Dom Baumer (vol. i., pp. 299-300)
that the fifth century, at Rome as elsewhere, was a period of great
liturgical activity, while the seventh and eighth centuries were, viewed
from this point of view, a period of decline" (Baudot, _op. cit._,
p. 53). The labours of St. Benedict probably were continued and perfected