Donna Seger has a nice, illustrated essay on some of the nineteenth and twentieth-century maps on which octopoi are used to warn of the creeping and insidious territorial and cultural expansion of certain states. She pulled this one from the University of Toronto website:

It's all a matter of perspective: Russia was often mapped as an octopus, sending its tentacles across Europe, but so was Japan and Britain, Germany and Austria, and also urban landlords. Pretty pictures, too!

h/t Mike Robinson: visiting OML fellow (2001-2), curator of the 2009 OML exhibition, The Coldest Crucible, and owner of the wonderful blog Time to Eat the Dogs on the history of exploration.