Simplify the following text for a Grade 9 native English-speaking person.
Original: In his second year , Ramesses II decisively defeated the Shardana or Sherden sea pirates who were wreaking havoc along Egypt 's Mediterranean coast by attacking cargo-laden vessels traveling the sea routes to Egypt .
Simplified: In his second year , Ramesses defeated the Sherden sea pirates . They were causing problems along Egypt 's Mediterranean coast by attacking cargo-laden vessels on the sea routes to Egypt .