STEFAN KANCHEV is, to my mind, the preeminent figure in mark making in the modern age. No offense to all you Paul Rand disciples. Born in 1915, Kanchev was the son of an iconographer and a student of Bulgarian folklore and traditions — which served as inspiration for much of his design work. In total, he is credited with authoring some 1,600 brandmarks in his lifetime and was named “National Artist” of Bulgaria. For more context and biographical info, not to mention a look at his impressive postage stamp and book cover collections, visit his official website.
UPDATE: The good-hearted folks over at Logoblink have put together an extremely comprehensive PDF about the life and work of Mr. Kanchev. Download it here (~30MB).