How did you get your brand into distributors?

I’m curious how other brand owners approach this.
A few years ago, we reached a point where we had a solid brand online and wanted to expand into offline/international distribution.
The obvious options seemed to be retail or distributors.
We decided to focus on distributors first.
Honestly, I underestimated how much persistence it would take.
For the UK market, it started with one trade show.
Then came roughly six months of weekly follow-ups.
Calls.
Emails.
Samples.
More calls.
More emails.
And yes, we paid for the samples ourselves.
Eventually, we got to the point where we were working with around 90% of the major distributors in our niche in the UK.
The funny part is that I initially thought my English might be a serious problem.
English isn’t my native language, and while I could communicate, I definitely wasn’t some smooth salesperson negotiating deals in perfect English.
But I learned something pretty useful:
You don’t need perfect English to sell.
You need to be able to explain what you’re offering, understand what the other person needs, and — probably most importantly — actually make the next call.
Then another one.
And another.
I think that’s the part people underestimate when talking about distribution.
There usually isn’t one magical email or one perfect trade show that suddenly opens the market.
It’s a lot of boring, repetitive work that nobody sees.
For those of you who have taken an e-commerce brand into wholesale/distribution:
What worked best for you — trade shows, cold outreach, agents, or something else?