“agronomist Axel Alfthan (1862–1934) and veterinarian Kaarlo Gummerus (1840–1898) expanded Aspelin’s hypothesis, proposing that the horse population later diverged into Eastern Finnish and Mid-Finnish types, which had remained distinguishable as late as the turn of the 20th century. Photographs support these claims: the small Karelian horse was blocky and stout, with pronounced withers, a short neck and large head. The small horse from central Finland, on the other hand, was “more noble”, with a longer body, lighter neck and more refined head.“
“The earliest known documentation of Finnish trade in horses, both as imports and exports, dates to 1299, when Pope Gregory IX sent a letter of reprimand to the merchants of Gotland, who were selling horses to the non-Christianized Finns. Apparently the Finns succeeded in improving their horse population, as the predominant form of Finnish trade in horses eventually shifted from imports to exports. A Russian chronicle from 1338 mentions “Tamma-Karjala” (“Karelia of the Mares”), presumably denoting a place of good horse breeding. As early as in 1347, King Magnus IV saw it necessary to put limits to the horse exports from Karelia to Russia.“
https://www.sotasampo.fi/fi/photographs/page/sakuva_71745