Marvel Comics vs Kamen Rider
Connections:
Both were once ordinary humble men living out their civilian life (Steve Rogers was a sickly young man trying to make ends means in 1940's America and Takeshi Hongo was a gifted young science student with a promising future in modern Japan)
Given superhuman abilities through an experiment from good-natured scientists (Doctor Abraham Erskine and Professor Hiroshi Midorikawa respectively). However, said scientists who were killed by minor villains which motivated the heroes to vow to always be selfless and use their gifts to protect the innocence (Heinz Kruger and Man Spider respectively)
Both fight villains with crazy powers by just using martial arts and their enhanced physiologies
Both fought Nazi-inspired organizations (Hydra for Captain America and Shocker for Kamen Rider Ichigo)
Both fight alongside with their friends (Falcon/Samuel Wilson and the Winter Soldier/Bucky Barnes for Captain America and Kamen Rider Nigo/Hayato Ichimonji for Kamen Rider Ichigo)
Both are known for their uncompromising selfless, relentless, heroic and patriotic attitudes, fighting for truth and justice
Both carry a lot of reverence in their universes (Captain America being remembered as one of the earliest and greatest superheroes whereas Kamen Rider Ichigo being remembered as the first Kamen Rider)
Both are the pure symbols of hope and true heroism for generations in the real world(Steve being one of Marvel's earliest successes and inspiring generations of kids with his stories, whereas Kamen Rider Ichigo's show spurs the creation of the legendary Tokusatsu genre in Japan and inspiring a generation of kids with his stories)
Both are icons of their respective countries (America and Japan respectively)