Bakumatsu Gijinden Roman

Wildest adventures Funny characters+more background information about them Has that samurai athmosphere to it. 

It looks so similar to Lupin that I want to say "Monkey Punch, you're stealing from yourself!" 

In both series, there's a sense of action, drama, and adventure. Lupin and Roman have similar physical traits as well as personalities who starts in their respective series. The artwork from both series are somewhat similar in terms of character designs. They also have a similar atmosphere with that sense of thrilling fun and ridiculous gags thrown in at occasions.  

Roman does the same job as Gintoki does. They both help people. Gintama- Odd Jobs Bakumatsu Gijinden Roman- Helper. 

Both are set in the "past." Both leads seem to be ridiculous morons but still manage to beat the bad guys at the end of the day. They are comedies also and have a small team of people that help the main character.