History of General Relativity
- Wikipedia article on the development of relativity. Includes sections about observational tests and alternative theories.
- http://en.wikipedia.org/wiki/History_of_general_relativity

Scott Walter's Homepage
- Contains articles of the historian of science Scott Walter (Université de Nancy 2), including those on the history of special relativity, with a special focus on contributors other than Einstein (such as Poincaré, and Minkowski).
- http://www.univ-nancy2.fr/DepPhilo/walter/

Einstein, Nordström and the Early Demise of Scalar, Lorentz Covariant Theories of Gravitation
- About the development of general relativity, Einstein's early rejection of Lorentz-covariant theories of gravity, and Nordström's attempts at formulating just such a model. By J. D. Norton (University of Pittsburgh).
- http://www.pitt.edu/~jdnorton/papers/Nordstroem.pdf

Henri Poincaré and Relativity Theory
- Identifies the contributions made to the special theory of relativity by Poincaré and argues that the theory "has been created not by A. Einstein only but even to a greater extent by Poincaré." By A. A. Logunov.
- http://arxiv.org/abs/physics/0408077

Relativity Priority Dispute
- Wikipedia article about the various contributors to special and general relativity, and about the contentious questions of who has priority on the different ideas and concepts involved, and in how far Einstein was influenced by his contemporaries and pred
- http://en.wikipedia.org/wiki/Relativity_priority_dispute

History of Special Relativity
- Wikipedia article on the genesis and development of special relativity and its precursors.
- http://en.wikipedia.org/wiki/History_of_special_relativity

Olinto De Pretto
- Wikipedia article about the Italian industrialist and claims that he published the famous formula E=mc² two years before Einstein did.
- http://en.wikipedia.org/wiki/Olinto_De_Pretto

History Topic: Special Relativity
- Concise summary of the history of special relativity, from Maxwell and Lorentz to Einstein; from the MacTutor History of Mathematics Archive (University of St. Andrews).
- http://www-history.mcs.st-andrews.ac.uk/~history/HistTopics/Special_relativity.html

Of Pots and Holes: Einstein’s Bumpy Road to General Relativity
- Article tracing the history of general relativity, by the historian of science Michel Janssen (University of Minnesota).
- http://www.tc.umn.edu/~janss011/pdf%20files/potsandholes.pdf

Einstein's Articles in "Annalen der Physik"
- Website by the Max Planck Institute for the History of Science (Berlin) presenting the seminal articles on relativity and other subjects that Einstein published in the physics journal "Annalen der Physik"; also includes four introductory essays
- http://einstein-annalen.mpiwg-berlin.mpg.de/home

Einstein's Discovery of Relativity
- Essay by John Stachel (Boston University) which gives a concise account of Einstein's biography at the turn of the century, and attempts to reconstruct how he developed the special theory of relativity.
- http://www.aip.org/history/einstein/essay-einstein-relativity.htm

Einstein's Time
- A discussion of the differences in perspective between Einstein and Poincaré between Peter Galison (Harvard) and Graham Burnett (Princeton); main focus are the notions of time and simultaneity.
- http://www.aip.org/history/einstein/essay-einsteins-time.htm

History Topic: General Relativity
- An outline of the development of the theory, including a summary of relevant earlier work (from Aristotle to Maxwell); from the MacTutor History of Mathematics Archive (University of St. Andrews).
- http://www-history.mcs.st-andrews.ac.uk/HistTopics/General_relativity.html

The Mystery of the Einstein-Poincaré Connection
- Discusses the similarities and differences between the two men's versions of what is now known as special relativity. By Olivier Darrigol (CNRS, Paris), published in the journal Isis.
- http://www.journals.uchicago.edu/ISIS/journal/issues/v95n4/950404/950404.web.pdf

Einstein and Hilbert: The Creation of General Relativity
- Discusses the correspondence between the two, their priority dispute, and their amicable resolution of it. By Ivan T. Todorov.
- http://arxiv.org/abs/physics/0504179

Lost in Einstein's Shadow
- American Scientist magazine article describes the people whose work paved the way for the special theory of relativity. By Tony Rothman; also includes link to PDF version.
- http://www.americanscientist.org/template/AssetDetail/assetid/49611