Rudolf I
 1218-1291. Holy Roman emperor and king of Germany (1273-1291) who founded the Habsburg dynasty.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Rudolf I
 (ˈruːdɒlf) or Rudolph I
n (Biography) 1218–91, king of Germany (1273–91): founder of the Hapsburg dynasty based on the duchies of Styria and Austria
 Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
Ru•dolf
 (or Ru•dolph) I
  (ˈru dɒlf)  
 n.   1218–91, Holy Roman emperor 1273–91: founder of the Hapsburg dynasty. 
 Also called Rudolph I of Hapsburg. Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.