The original AEC Monarch was built from 1931 to 1939 at AEC's Southall works. The first version had payload of 7 tons (increased to tons from 1933) and was fitted with either an four-cylinder 5.1-litre diesel engine or an 80 hp four-cylinder 5.1-litre petrol engine. This was a robust and well-designed lorry, popular with both drivers and operators. The model was discontinued in the 1950s, although the name lived on into the 1970s in some export markets. TL 3513 (1934) KYE 402 (1949)