“Louis in London,” a live album from 1968, captures a lively Louis Armstrong in his late career

At the end of his career, every note Louis Armstrong sang still exuded joie de vivre.

That includes a live album called “Louis in London,” released Friday and billed in promotional materials as his “last major performance.” The 13-track set features recordings of Armstrong and a powerful five-piece backing band playing in front of a BBC audience on July 2, 1968. Armstrong’s chronic health problems soon worsened, and he died in 1971.

Almost half of the material on Louis in London is previously unreleased, and the album offers a snapshot of Armstrong at the height of his popularity. The performance came weeks after he hit number one in the UK charts with What a Wonderful World.

That song is included, its unabashed sentimentality defying headlines then and now. Armstrong also gets the room swaying to songs from back then, starting with a hearty rendition of his longtime theme song, “When It’s Sleepy Time Down South.”

The set is primarily a vocal album, dominated by Armstrong’s cheerful showmanship and his distinctive baritone. His voice dances through every tune, riding improvised flourishes that include wordless grunts, growls and gurgles. Even the simplest lyrics benefit from his unmistakable signature: he sings “Baby” like no one else.

Armstrong’s trumpet plays only a supporting role, but his still brilliant tone makes every performance an invigorating embrace. The supporting cast, both tight and loose, includes Tyree Glenn on trombone, Joe Muranyi on clarinet, Marty Napoleon on piano, Buddy Catlett on bass and Danny Barcelona on drums.

They form a parade of brilliant soloists on the two instrumental pieces, Dixieland versions of “(Back Home Again In) Indiana” and “Ole Miss.” The latter piece by WC Handy is considered the first composition that Armstrong played in public.

Armstrong sings “Hello, Dolly!” with an enthusiasm that has the crowd clapping along to the beat. Other highlights include “Mack the Knife,” with a bouncy groove that gradually builds in intensity, and “Rockin’ Chair” by Hoagy Carmichael, a theatrical vocal duet with Glenn. “One of the good old songs,” Armstrong says of the latter song.

The album ends with “When the Saints Go Marching In,” and when Armstrong’s final note adds a jazzy touch to the final chord, it’s a sound for the ages.