Art Davis, Lee Powell, and Bill 'Cowboy Rambler' Boyd did 6 films in PRC's short-lived 'Frontier Marshal' trio series.
Bob Livingston did 7 films from 1936-1943 (a 1936 Three Mesquiteers, 5 of PRC's 'Lone Rider' series, and a non-western).
Johnny Mack Brown in 7 westerns and one non-western in 1935-1937.
Fred Scott in 6 singin' cowboy oaters in 1937-1938 for Spectrum.
Kermit Maynard in 4 RCMP mountie adventures in 1935 for Ambassador/Maurice Conn.
Charles Starrett in the mountie film UNDERCOVER MEN (J. R. Booth/Dominion, 1935).
Ken Maynard in 2 films in 1939.
James Newill in a Renfrew mountie adventure in 1939.
Tex Fletcher in his only starring film in 1939.
Art Jarrett, Lee Powell, and Al St. John in TRIGGER PALS (Grand National, 1939), a failed attempt at creating a new trio series.
Rex Bell in 1 film in 1936.
Herb Jeffries in 1 film in 1937.
A Jack Randall Monogram oater in 1938.

The film quantities are mostly westerns, but these guys worked in other features for Newfield, and those are included in their film totals. ❋  = quantity includes stunting and doubling.

Augie Gomez
31 films from 1940-1956

Charles 'Slim' Whitaker
29 films from 1936-1946

Jack Ingram
29 films from 1937-1947

Oscar Gahan
28 films from 1936-1943

George Chesebro
27 films from 1936-1946

John Merton
26 films from 1936-1956

Hal Price
26 films from 1937-1945

Chick Hannan/Hannon
23 films from 1937-1944

Artie Ortego
23 films from 1935-1951

Milt Kibbee
23 films from 1941-1951

Frank McCarroll
22 films from 1935-1945 ❋

John Elliott
22 films from 1935-1944

Reed Howes
21 films from 1938-1944

Ed Cassidy
21 films from 1935-1950

Lew Meehan
21 films from 1936-1941

Hank Bell
21 films from 1936-1945

Horace B. Carpenter
21 films from 1935-1945

Frank La Rue
20 films from 1937-1943

Roy Bucko
20 films from 1936-1952

Forrest Taylor
20 films from 1937-1943

John 'Lefty' / Bob Cason
20 films from 1942-1946

Sam Newfield's Republic credits amount to twenty two films during 1935 - 1938. However, those credits are misleading.

In actuality, he worked directly for Republic only one time, co-directing (with Mack V. Wright) the Three Mesquiteers' ROARIN' LEAD (Republic, 1936).

Republic Pictures was formed in 1935. During their formative years, the company contracted with outside producers for additional films to supplement their in-house production and bolster their release schedules.

A. William Hackel was the boss/owner of Supreme Pictures Corporation and had Johnny Mack Brown and Bob Steele doing westerns. Hackel signed a deal with the new Republic organization to continue both series, and eight Browns and sixteen Steeles were released by Republic during 1936 - 1938. Of those twenty four, seventeen were helmed by Sam Newfield (six Johnny Mack Browns and eleven Bob Steeles). Newfield got his paycheck from Hackel.

Republic also distributed RACING LUCK (1935), BURNING GOLD (1936), GO-GET-'EM HAINES (1936) and FEDERAL AGENT (1936), all starring William Boyd (and these were lensed prior to Boyd becoming Hopalong Cassidy). Newfield directed these for producer George Hirliman (Winchester Pictures).

In a nutshell, Sam Newfield did one real Republic production and twenty one "acquired by Republic" films.

(Courtesy of Les Adams)

(Courtesy of Les Adams)