Possible Clues:

• Informal (language)
• Local-style copper in spring first to apprehend ringleader
• A ruler can set out to follow up very popular speech
• The special talent of Londoners might be expressed thus: new city in old one's native style
• Jargon for Vergeltungswaffe: nuclear modification on a rocket head
• Perhaps French artist, Lord and clergyman retired
• Characteristic language
• Local dialect
• Native tongue - dialect