"German airline Lufthansa said Sunday that its services were more or less back to normal after a four-day walkout by pilots, but unions warned of further disruptions, possibly over the Easter holidays."
"In all, around 220,000 passengers were hit by the four-day walkout, Lufthansa said."
Read more: http://www.businessinsider.com/afp-lufthansa-says-services-back-to-normal-after-pilots-strike-2015-3
Seems the European airlines go on strike more than American airlines. I remember a few years back when Alitalia was threatening a strike, much to my displeasure on a planned trip to Rome!
Ahhhh, the joys of flight travel.