The defender qualifies for Portugal through her father, Joaquim, and was contacted by them when she was younger after impressing in the Lionesses’ youth teams.
Bronze has now admitted that she considered switching allegiances too, due to her frustration of wanting to play senior international football.
“[Portugal] got in touch when I was 16,” she explained.
“I turned around and said to my mum if I don't make the England team before my 22nd birthday, I'm off to play for Portugal.
“My mum always just says whatever makes you happy. My dad wasn't bothered either.
“But I was doing everything I could. I was playing well on the pitch and I thought I deserved a call up and it took a long, long time.
“When I was younger, it's not as easy as it is now for these young ones,” she added.
“But I fought my way into the squad. England was always the dream.
“I knew I could go and play for Portugal and I would have loved it as much.”
Bronze’s first call-up for England came just before she turned 22, making her debut against Japan in June 2013 before going to the summer’s European Championships as an unused member of the squad.
Despite making close to 80 appearances for the Lionesses since, Tuesday will be the first time Bronze has faced Portugal.
The two teams met in the 2017 Euros, but Mark Sampson rested most of his team with England already qualified for the quarter-finals, meaning Bronze did not feature.
“We've never played in Portugal and my Portuguese family have never watched me in an England shirt,” the 27-year-old said.
“My dad is Portuguese and he came [to watch England play Brazil on Saturday].
“He's flying across [to Portugal] and he's basically taking all his family. My auntie, my uncle, my grandma and some of my dad's cousins are coming.
“Obviously I'm excited for that, but it’s the same when I play in the North East,” she continued, with the Lionesses having played in Middlesbrough at the weekend.
“My family live here so they get to come, so I was excited for both games this week. I’m excited to play against Portugal.”
The game will not just be a sentimental friendly for Bronze though, but an important fixture for England, who are looking to end their five-game winless run.
It is the Lionesses’ worst run since 2013, which ended in them finishing bottom of their group at the Euros and then-manager Hope Powell being sacked.
“We know we're one of the best teams in the world, but the results haven't showed that necessarily,” Bronze added.
“I think we just need to be playing more games together.
“You look at the front three [against Brazil] and they all play in different leagues to each other - let alone different teams.
“We've got to develop that understanding together. It’s started to click, but it's just the end product still.”