John Matze, a software engineer who was Parler’s co-founder and chief executive, said earlier this month that Ms. Mercer had effectively fired him over disagreements on how to run the site. Ms. Mercer hired Mark Meckler, a leading voice in the Tea Party movement, to replace Mr. Matze.
Before the site’s return on Monday, Parler executives had said they were rejected by multiple web-hosting companies that either feared a public-relations backlash or a cyberattack if they agreed to support the site.
On Monday, data behind Parler’s website showed that it was connected to an Ohio firm called CloudRoute and a Los Angeles firm called SkySilk, according to Doug Madory, an internet-infrastructure expert. CloudRoute’s chief executive, Andre Temnorod, said in an interview that his company only appeared in that data because it sold technology to SkySilk, a web-hosting provider. “SkySilk is our customer and Parler is SkySilk’s customer,” he said. SkySilk did not immediately respond to requests for comment.
About a week after it went offline, Parler set up a basic webpage for people trying to visit its social network with simple messages that said the company was working to get back online and notes of support from conservatives like Sean Hannity, the Fox News host, and Senator Rand Paul, Republican from Kentucky.
That page, which was so simple it could have been hosted from a single laptop, still required cybersecurity protections to stay online, in part because Parler has been under attack from internet vigilantes who believe it helped play a role in the Capitol riot.
To stay online, Parler got help from DDoS-Guard, a Russian firm, which raised concerns among some internet researchers that the Russian government could surveil Parler users. Parler also partnered with Epik, a Seattle company, for its domain registration, a basic service of the internet. Epik has helped support other fringe sites that lost their support from other companies, including the Daily Stormer, a neo-Nazi site.
Mr. Matze founded Parler in 2018 with a fellow programmer outside of Las Vegas, aiming to tap into growing discontent with Silicon Valley, particularly among people on the far right, who were finding themselves increasingly restricted on mainstream social networks as Facebook and Twitter cracked down on hate speech, threats and misinformation.