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Empire and Papacy - http://www.fordham.edu/halsall/sbook1l.html
An introduction and collection of sources from the Medieval Sourcebook on the relationship between the Pope and the Holy Roman Emperor. |
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Conflict of Investitures - http://www.newadvent.org/cathen/08084c.htm
Article from the Catholic Encyclopedia. |
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The Investiture Conflict - http://the-orb.net/textbooks/nelson/investiture.html
Lecture by Lynn Nelson in the Online Reference Book for Medieval Studies. |
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The Owl, The Pussycat and the Investiture Controversy - http://www.vlib.us/medieval/lectures/investiture.html
Professor emeritus Lynn H. Nelson explains the Investiture Controversy in medieval dialogue form. |