:: "Wałęsa" does not exist in the English language.  Period.  Seriously, Americans use diacritics for one of two reasons, 1) World of Warcrafters who like unique names and 2) Mötley Crüe fans. - Oy! Come on Tarc! In addition to all the World of Warcraft players who, for obviously obvious reason, name their panda monks "Lech Wałęsa" (what. the. fuck.???) and  that Motley Crew drummer who exploded whose name was Lech Wałęsa (wtf^2), you forgot that third reason - it's freaking used by Britannica which is neither WoW nor Motley Crue. And other sources. Again, you're just making shit up and projecting your own conception of reality - which is more or less the "my friends don't use diacritics so it's not English dammit and I'm a lazy bum, so it's like "Walesa", dude!". Give it a break. "Wałęsa" very much does exist in the English language. And it certainly should be used in what claims to be a reliable reference work. Period. Seriously. Get over it. Mannnnnn.