Henry ruled jointly with his brothers Eric II and Albert VII and his uncle Balthasar from 27 December 1503.

Albert repeatedly advocated the division of the territories of Mecklenburg, and this was agreed to in the House Treaty of Neubrandenburg, sealed on 7 May 1520.

The treaty stipulated that Henry rule in Schwerin and Albert in Güstrow, without a de facto division of the country.

It was during the reign of the brothers Henry and Albert that Martin Luther launched the Reformation, which quickly found supporters in Mecklenburg.

Naturally, his position led him to give the new doctrine a firm external and internal organization, so he asked Superintendent Johann Riebling, whom Luther had recommended to him in 1537, to draft a Church Order, a Catechism and an Agenda.