Russian tsar Ivan IV declared the establishment of the kingdom during the Livonian War of 1558–1583, but it never functioned properly as a polity.

Magnus left Moscow with a Russian army with the intention of conquering Swedish-controlled Reval, but called off the siege in 1571 after failing to capture the city.

On 10 June 1570, Magnus, Duke of Holstein arrived in Moscow with the approval of his older brother Frederick II of Denmark, where he was crowned the king of Livonia.

[3] In 1578, having lost Ivan's favor and getting no support from his brother, Magnus called on the Livonian nobility to rally to him in a struggle against foreign occupation.

Magnus spent the rest of his life at the castle of Pilten in the Bishopric of Courland, where he died as a pensioner of the Polish crown in March 1583.