There is no special icon for Google today! What the hell! Don't those commies up there in Mountain View know what an important day today is? Well, the fact is that nearly any day you pick will have some event of historical significance to examine. Google can't celebrate every anniversary of every thing -- and if it does, then the things that it does celebrate lose their cachet by dilution.
Today, for instance, is the seven hundred and ninety-fifth anniversary of Magna Charta. On June 15, 1215, a principle of civilization which had been absent from Europe nearly eight centuries returned to force, and that, more than anything else, propelled England, and then the rest of Europe in its wake, out of the medieval period and forward, ultimately, to modernity.
The Great Charter itself did not all that much to establish liberties or politically enfranchise individuals. The very King who issued it violated it within only a few years of signing it, faithlessly, strictly to quell a rebellion. And even though it was re-issued several more times, it is now completely superceded both in England and in all of England's many daughter and sister countries.* Still, if there is a bedrock principle, a foundation upon which we can say political legitimacy is built, this is it: the government is subject to the rule of law. We Americans too easily take that concept for granted, and ought to remember that there are yet many places in the world where that statement is not true. None of which you'd particularly want to be in for very long.
I realize that in 2015, it will be the octocentennial of that momentous day when King John kept his head by giving up a minute amount of power, but what is the 795th anniversary of a thing called?
* "Sister countries." That one's for you, Scotland.