Fleetwood, bidding to become the first Englishman to win the title since Nick Faldo in 1992, picked up four birdies on the back nine to join the towering Lamprecht on five under par at a sun-kissed Hoylake.
Roared on by the galleries at a course 30 miles from where he was born, Fleetwood made the perfect start to his bid for a first major crown.
"It was very cool and I think you can't ask for more from the fans and the support. They were so great to me today," the world number 21 told reporters.
"Such a special opportunity to play so close to home. I am glad I gave them some good golf to watch. To be in the clubhouse now, to have played so well, it's a lovely feeling."
Lamprecht, six foot eight inches tall, drove with great power and accuracy in a round including seven birdies and two bogeys.
"It's pretty surreal," he said. "It's nice to see a lot of work behind the scenes pay off. It's something I haven't dreamt of yet."
American Stewart Cink, Open champion in 2009, rolled back the years with a flawless 68 to finish at three under, level with compatriot Wyndham Clark who won last month's U.S. Open.
Jordan Spieth, the 2017 Open champion, shot 69 and world number one Scottie Scheffler, Brooks Koepka, Patrick Reed, Xander Schauffele and Patrick Cantlay 70s to add a strong American presence to the leaderboard.
England's Matthew Jordan, who had the honour of hitting the opening tee shot at Royal Liverpool Golf Club where he has been a member since the age of seven, also carded 69.
"Amazing, I'm kind of running out of words to describe it," the 27-year-old told reporters. "It was crazy, mental, loud, everything that I could have wished for."
It was a mixed day for defending champion Cameron Smith whose 72 was sprinkled with five bogeys and four birdies.
"There was lots of good today for myself, but probably just as much or even more bad. Nothing really to work on, to be honest. It still feels really good," the Australian said.
World number two Rory McIlroy, favourite to win his fifth major at the course where he lifted the Claret Jug in 2014, was among the late starters and he settled his nerves with a brilliant approach shot to birdie the second hole.
