Rather unusual Austrian Knickerbockers made from leather. Judging from the discernible details and cut (and braces) certainly 30-50's. Clearly not the usual "Lederhosen" pattern.
http://www.ebay.de/itm/ANTIKE-LEDERHOSE-/310673761073?
http://www.ebay.de/itm/ANTIKE-LEDERHOSE-/310673761073?