It is eminently right and proper that the Government of the United States should give earnest and substantial evidence of its just appreciation of the services of the patriotic men who when the life of the nation was imperiled entered the Army and Navy to preserve the integrity of the Union, defend the Government, and maintain and perpetuate unimpaired its free institutions.
It is therefore directed--
First. That in appointments to office in the several Executive Departments of the General Government and the various branches of the public service connected with said Departments preference shall be given to such meritorious and honorably discharged soldiers and sailors--particularly those who have been disabled by wounds received or diseases contracted in the line of duty--as may possess the proper qualifications.
Second. That in all promotions in said Departments and the several branches of the public service connected therewith such persons shall have preference, when equally eligible and qualified, over those who have not faithfully and honorably served in the land or naval forces of the United States.
Andrew Johnson, Executive Order Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/202543