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The ratio $\epsilon'/\epsilon$ measures the size of the direct CP violationin $K_L\to\pi\pi$ decays $(\epsilon^\prime)$ relative to the indirect onedescribed by $\epsilon$ and is very sensitive to new sources of CP violation.As such it played a prominent role in particle physics already for 45 years.Due to the smallness of $\epsilon'/\epsilon$ its measurement required heroicefforts in the 1980s and the 1990s on both sides of the Atlantic with finalresults presented by NA48 and KTeV collaborations 20 years ago. Unfortunately,even 45 years after the first calculation of $\epsilon'/\epsilon$ we do notknow to which degree the Standard Model agrees with this data and how large isthe room left for new physics contributions to this ratio. This is due tosignificant non-perturbative (hadronic) uncertainties accompanied by partialcancellation between the QCD penguin contributions and electroweak penguincontributions. While the significant control over the short distanceperturbative effects has been achieved already in the early 1990s, with severalimprovements since then, different views on the non-perturbative contributionsto $\epsilon'/\epsilon$ have been expressed by different authors over lastthirty years. In fact even today the uncertainty in the room left for NPcontributions to $\epsilon'/\epsilon$ is very significant. My own work on$\epsilon'/\epsilon$ started in 1983 and involved both perturbative andnon-perturbative calculations. This writing is a non-technical recollection ofthe steps which led to the present status of $\epsilon'/\epsilon$ includingseveral historical remarks not known to everybody. The present status of the$\Delta I=1/2$ rule is also summarized. This story is dedicated to Jean-MarcGerard on the occasion of the 35th anniversary of our collaboration and his64th birthday.

The $\epsilon'/\epsilon$-Story: 1976-2021