П_Пашкевич
С какой-то стороны, с Ирландией куда проще, чем с бриттами. Про них пишут хоть что-то.

The early Irish sources make a clear distinction between horses used for riding and those used for working. Kelly (1997: 96) indicates that the
riding of horses was the prerogative of the nobility and well-off free farmer class. The higher one’s status the more horses one was expected to own. Thus, a typical lord would be expected to own one riding horse and four others for lesser tasks (Kelly 2005: 31). The law tracts indicate that horses were regarded as being of much greater value than milk cows (Kelly 2005: 32) despite the fact that this was a society where the possession of cows comprised the basis of one’s wealth.
Women rarely rode a horse but were instead transported in chariots. The law tracts make it clear that roads were maintained with chariots in
mind. A route way which could boast the title "highway” was wide enough to allow two chariots to pass each other while a “road” could accommodate one chariot and two horsemen passing
(Kelly 1997: 538).

В принципе, я могу всю пдфку скинуть, но она небольшая и вообще статья про лошадей в ранней Ирландии, про 5-9 века там страницы две, наверное.