No Twitter account has yet been announced for the Duke and Duchess of Sussex.
The gallery post also included images of the royal couple together, as well as images of causes the couple are passionate about, including conservation and the British Armed Forces.
Harry and Meghan claimed the record from K-Pop star Kang Daniel, who reached the 1 million follower milestone with a selfie in January.
Though we think the Duchess always looks gorgeous, when photos of her in the dress emerged, she was unfortunately subjected to uncalled-for criticisms, with people branding her look "inappropriate" and "disrespectful" over on the Kensington Palace Instagram page.
Harry's cousin, Princess Eugenie posted on her personal account welcoming her family to the social media platform saying, "Welcome cousins".
The official account, sussexroyal, will be used for "important announcements" and to share work that "drives" them.
Meanwhile, the most-followed Instagram account in the world is now Instagram itself, followed by footballer Cristiano Ronaldo. Take a look at some of their pictures from their first post: The account will serve as a place where the royal couple can update their followers on major news and promote causes close to their hearts.
"We thank you for your support, and welcome you to @sussexroyal".
Now that Markle and Prince Harry have their own social media account, their fans opted to unfollow the Kensington Palace and this resulted to Middleton and Prince William losing followers.