In a statement on Wednesday, Kensington Palace said: "These new patronages, which have been given to The Duchess by Her Majesty The Queen, closely align with Her Royal Highness' longstanding passion for sport and the lifelong benefits it can provide, both within our communities and on an individual level."
The Duke and Duchess of Sussex had to give up their patronages following their decision to step back as senior royals in March 2020.
WATCH: Kate replaces Prince Harry as rugby patron
Kate is a known sports enthusiast and has attended rugby matches in the UK, as well as the Six Nations tournament in Paris in 2017. And in a piece for Vanity Fair in 2014, the Duchess' younger sister, Pippa Middleton, wrote about her family's love for the sport: "Rugby was a big thing for our family, and the focal point was international matches, which were often played on Saturday afternoons and were as much social as sporting occasions.
"We'd plan our weekends around the big matches, a quick bite to eat at halftime or lunch on our laps, typically a chicken potpie or something equally cosy and English. If we lost, my dad would be in a state of despair for the rest of the afternoon, as if he'd actually lost the game himself."
In a statement, Ralph Rimmer, Chief Executive of the Rugby Football League said: "We are truly honoured by the appointment of The Duchess of Cambridge as the Rugby Football League's Royal Patron. We are delighted to welcome her as we prepare to host Men's, Women's, Wheelchair and Physical Disability Rugby League World Cups in England this autumn.
"Our sport's history has been built on a commitment to tackling inequalities and we honour that through our focus on having a positive social impact well beyond the pitch. We look forward to working with The Duchess in the years to come, and I know all levels of our sport will welcome her to the Rugby League family."
Harry, William and Kate at a Six Nations match in 2007
Meanwhile, Bill Sweeney, Chief Executive of the Rugby Football Union said: "It is a great honour to welcome The Duchess of Cambridge as our Patron. Our aim is to enrich lives, introduce more people to rugby union, develop the sport for future generations and create a successful thriving game across the country.
"As rugby clubs have re-opened across the country, players, officials, and volunteers are celebrating being back in the game together, and we know the support of The Duchess will be greatly valued from our grass roots clubs and fast-growing women and girls' game, right up to our elite Men's and Women's England teams."
The Cambridges at a Six Nations match in Paris in 2017
Established in 1895, The Rugby Football League is the national governing body for Rugby League in the UK – covering all forms of grassroots and the professional game, including women's and wheelchair rugby.
The Rugby Football Union, founded in 1871, is the national governing body for grassroots and elite rugby union in England and with 1,900 member clubs is one of the largest sports organisations in the country.
There's a chance we could see Kate and husband, Prince William, get competitive later this month. The Duke is patron of the Welsh Rugby Union and Wales will take on England at Twickenham on Saturday 26 February in the Guinness Six Nations 2022.
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