On 20/26 April 1220, the German princes assembled at Frankfurt elected Henry King of the Romans, for which the Emperor issued Confoederatio cum principibus ecclesiasticis, favoring the prince-bishops.

[4] "The chief Princes present at Frankfort were the Archbishops of Mayence, Cologne, Treves, and Magdeburg, several Bishops, the Dukes of Bavaria and Brabant, the Landgrave of Thuringia, the Margraves of Namur and Baden, the Counts of Holland and Cleves, and the officials of Frederick's court.

However, Pope Honorius III did not recognize the election and also deprived Henry of his rights over the Sicilian kingdom, because he (just as his predecessor) wanted to prevent the union of both countries.

After Frederick II returned to Italy in 1220, Henry was placed under the tutelage of Archbishop Engelbert I of Cologne,[4] who crowned him German king on 8 May 1222, in Aachen.

In Nürnberg on 29 November 1225, by order of his father, Henry married Margaret of Babenberg, daughter of Duke Leopold VI of Austria, a woman seven years older than he was.

The German princes, angered by his city-friendly policies, forced him however to issue in Worms on 1 May 1231 the Statutum in favorem principum, directed against the cities, and by their complaints turned Frederick II against his son.

In the following year he entered into a conflict with the House of Wittelsbach and subdued Otto II of the Palatinate, the son of Duke Louis of Bavaria.

The princes adopted a wait-and-see stance, while Henry's forces were stuck in fights with the Lords of Hohenlohe, Margrave Herman V of Baden, and the City of Worms.

Frederick II reacted to the weakening of the royal power originated by his dispute with his son, among other things, with the diet in Mainz on 25 August 1235, which for first time passed a law on the public peace (German: Landfriedensgesetz) and fundamentally reformed the Regalia.

The manuscript includes numerous shields with coats of arms upright or inverted, indicating births, coronations, or deaths of kings, nobles, clerics, and knights.'

In this manuscript, Conrad's shield with the coat of arms, at death, is a double headed eagle and in chief a red point within a part of, what it looks like, the moon.

On the original Codex Manesse the picture shows: the eagle faded out and 'overwritten' with a cross may resamble the time of an enforced abdication of Henry VII by his father Frederick II.

Long time in his father's shadow and disparaged as "Parentheses Henry", several historians in recent years have adopted a more positive view of his Hohenstaufen policies.