What is Ferdinand I, Holy Roman Emperor?
{{Infobox royalty|name=Ferdinand I|house=[[House of Habsburg|Habsburg]]|predecessor4=Charles I|successor4=Maximilian II (Austria proper)<br>[[Charles II, Archduke of Austria|Charles II]] (Inner Austria)<br>[[Ferdinand II, Archduke of Austria|Ferdinand II]] (Further Austria)|spouse={{Marriage|[[Anne of Bohemia and Hungary]]|26 May 1521|27 January 1547|end=died}}|issue=|issue-link=#Marriage and children|issue-pipe=see detail...|father=[[Philip I of Castile]]|succession4=[[Archduke of Austria]]|mother=[[Joanna of Castile]]|birth_date=10 March 1503|birth_place=[[Alcalá de Henares]], [[Crown of Castile|Castile]], Spain|death_date={{death date and age|1564|7|25|1503|3|10|df=y}}|death_place=[[Vienna]], [[Archduchy of Austria|Austria]]|place of burial=[[Prague]], [[St. Vitus Cathedral]], [[Bohemia|Czech Republic]]|religion=[[Roman Catholicism]]|reign4=21 April 1521 – {{nowrap|25 July 1564}}|successor3=Maximilian II|image=Hans Bocksberger der Aeltere 001.jpg|successor=[[Maximilian II, Holy Roman Emperor|Maximilian II]]|caption=Portrait by [[Hans Bocksberger der Ältere]]|succession=[[Holy Roman Emperor]]|reign=27 August 1556 – {{nowrap|25 July 1564}}|coronation=14 March 1558, [[Frankfurt]]|cor-type={{nowrap|Proclamation}}|predecessor=[[Charles V, Holy Roman Emperor|Charles V]]|succession2=[[King of the Romans]]<br>[[King in Germany]]|predecessor3=[[Louis II of Hungary|Louis II]]|reign2=5 January 1531 – {{nowrap|25 July 1564}}|predecessor2=Charles V|successor2=Maximilian II|succession3=[[King of Hungary]], [[King of Croatia|Croatia]], and [[King of Bohemia|Bohemia]]|coronation3=3 November 1527 ([[Kingdom of Hungary|Hungary]])<br>24 February 1526 ([[Kingdom of Bohemia|Bohemia]])|cor-type3=[[Coronation]]|reign3=1526 – {{nowrap|25 July 1564}}|signature=Fernando I of Holy Roman Empire signature.svg}} '''Ferdinand I''' ({{lang-es|Fernando I}}; 10 March 1503 – 25 July 1564) was [[Holy Roman Emperor]] from 1556, [[King]] of [[Bohemia]], [[Hungary]], and [[Croatia]] from 1526, and [[Archduke of Austria]] from 1521 to 1564.<ref nam