Early 19th century; earliest use found in Robert Southey (1774–1843), poet and reviewer. From rascal + -ry. Compare earlier rascality and also rascalment.
Definition of rascalry in US English:
rascalry
noun
1Rascals collectively. Compare "rascality". rare.
2Rascally behaviour. "rascality".
Origin
Early 19th century; earliest use found in Robert Southey (1774–1843), poet and reviewer. From rascal + -ry. Compare earlier rascality and also rascalment.