Why are articles of confederation historically important?

The Articles of Confederation served as the written document that established the functions of the national government of the United States after it declared independence from Great Britain.

Explanation:

The Articles of Confederation and Perpetual Union was an agreement among the 13 original states of the United States of America that served as its first constitution. ... A guiding principle of the Articles was to preserve the independence and sovereignty of the states.

abraham lincoln  (february 12, 1809  – april 15, 1865) was an american statesman, politician, and lawyer who served as the 16th  president of the united states  from 1861 until  his assassination  in april 1865. lincoln led the nation through the  american civil war, its bloodiest war and its greatest moral, constitutional, and political crisis.[2][3]  he preserved the  union,  abolished slavery, strengthened the  federal government, and modernized  the u.s. economy.

they change the constitution.