Original sentence: As early as the 15th century, the heraldic charging knight on horseback became the coat of arms of the Grand Duchy of Lithuania and of its central part - the Duchy of Vilnius.By the 14th century, the charging knight on horseback with a sword had begun to feature in an heraldic shield, first in Yahayla's seal in 1386 or 1387, and also in the seal of Vitautas in 1401.It features on the seal of the Grand Duke of Lithuania, Algirdas, which marks a document dating from 1366.The symbol of the charging knight on horseback passed down through the generations: from Algirdas to his son, Grand Duke Jogaila (ruled 1377 - 1392), then to Grand Duke Vytautas ruled 1392 - 1430) and to others.We know that at the Battle of Grunwald (1410), where the united Polish-Lithuanian army crushed the army of the Teutonic Knights (thus putting an end to the Knights' eastward expansion) thirty Lithuanian and Ruthenian regiments out of a total of forty fought under banners flying the sign of the Pahonia
Edited sentence: As early as the 15th century, the heraldic charging knight on horseback became the coat of arms of the Grand Duchy of Lithuania and of its central part - the Duchy of Vilna.By the 14th century, the charging knight on horseback with a sword had begun to feature in an heraldic shield, first in Yahayla's seal in 1386 or 1387, and also in the seal of Vitaut in 1401.It features on the seal of the Grand Duke of Lithuania, Algerd (, Alhierd, ruled 1345 - 1377), which marks a document dating from 1366.The symbol of the charging knight on horseback passed down through the generations: from Algirdas to his son, Grand Duke Yahayla (ruled 1377 - 1392), then to Grand Duke Vitawt (, Vitaut, ruled 1392 - 1430) and to others.We know that at the Battle of Grunwald (1410), where the united Polish-Lithuanian army crushed the army of the Teutonic Knights (thus putting an end to the Knights' eastward expansion) thirty Belarusian and Lithuanian regiments out of a total of forty fought under banners flying the sign of the Pahonia