If all goes as planned, Ralph Brennan will officially take ownership of the historic Napoleon House (500 Chartres St., 504-524-9752; napoleonhouse.com) at the end of the month. One of the local restaurateur’s chief lieutenants will be on the job there much sooner, however.

Brennan has tapped Chris Montero, executive chef and general manager of his Old Metairie restaurant Cafe B, to run Napoleon House when he takes over on April 30. For the next few weeks, Montero plans to ensconce himself in the French Quarter landmark, essentially shadowing proprietor Sal Impastato as his long tenure at the helm winds down.

“Really, the key is going to be learning from Sal, seeing what he does, how he runs the place,” said Montero.

It’s an important step, he explained, because the approach that Brennan’s company has planned for the future of Napoleon House starts by hewing close to its traditions and touchstones.

Serving as both chef and general manager, Montero’s marching orders are to keep what’s essential to Napoleon House and also to keep it around for the future. There will be building repairs, and behind the scenes some business systems and operations may be up for change. Eventually Montero will rework the menu.

Through it all, he stressed, the process would be gradual. Napoleon House won’t even close for the change in ownership, which is slated for one of the busiest weeks of the year for the restaurant with crowds in town for the New Orleans Jazz & Heritage Festival.

“We don’t intend to change a thing about what everyone knows about Napoleon House,” Montero said. “That’s what we want to preserve and carry forward.”

That may entail a balancing act. The qualities that distinguish Napoleon House have burned in over the century that the Impastato family has been in business here. The property itself is a mansion built for a mayor, Nicholas Girod, in 1814 when the city was just emerging from its colonial era. The Impastatos first operated a grocery here in 1914, when the French Quarter was a bastion of Italian immigrants. From there, Napoleon House developed into a bar, then into a restaurant and finally into something of an emblem for old New Orleans as its patina deepened and its contrast to more modern modes of business lengthened.

Famous for its Pimm’s Cup cocktails, muffulettas and a soundtrack dedicated to classical music, Napoleon House picked up other unusual quirks along the way that may not be considered so essential to its character.

For instance, the business has for years now stayed closed on Sundays and on Mondays it has closed early, before dinner time. Operating hours are one area up for evaluation, Montero said. The Napoleon House property is also much larger than even some of regulars may imagine, extending through upstairs rooms now used for private parties and through wings that currently are not open to the public. Montero said in the future he intends to make more of the potential banquet and event spaces here.

Just a block away, Brennan recently completed a massive and lengthy renovation of Brennan’s Restaurant, though his approach to Napoleon House will be much gentler. That’s one reason he said Montero was an obvious choice for the job.

“I want to go in and learn the business and Chris understands that,” Brennan said. “I want to keep it the same and stable as long as possible. Chris is one I trust a lot. He’s not going to go in there and try to stir things up.”

Now 57, the New Orleans native worked broadly across the hospitality industry before devoting himself, at age 40, to becoming a chef. He learned his chops on the job, and joined the Ralph Brennan Restaurant Group in 1999 as chef at its former French Quarter restaurant Bacco.

In 2011, he moved to Café B, where he developed a menu that is contemporary but still has plenty of traditional Creole influences.

“If I’m passionate about food, I’m even more passionate about New Orleans history,” said Montero. “That’s why I’m so excited to be part of what we’re doing at Napoleon House.”

Meanwhile, Steven Marsella, executive chef of Brennan’s other Metairie restaurant, Heritage Grill, will take over for Montero at Café B.

Follow Ian McNulty on Twitter @IanMcNultyNOLA.