UK Car Sales By Brand : 1970-74

This was a time of consolidation by import makes as they all had gains in this period while the top 4 UK car makers went nowhere. I did hear that at the time brands such as Ford cut all their smaller dealers, effectively handing them over to import brands. That got them a foothold, which they built on. I'm not sure how true that was.
Local car makers: During this five year time frame, the Ford Cortina took over from the BL 1100/1300 at the best selling car. The Morris Marina came along and got to 2nd in 1973, but couldn't quite get to the top. The Cortina was ably backed up by the Escort. Hillman had success with the Avenger and Hunter models. Vauxhall relied on the Viva as it's lone top 10 car. The Austin Maxi was a top 10 car at the time too.

The Ford Cortina was winning over the UK

Imported car makers: Datsun (Nissan) was a big winner, coming from obscurity to 5th. The Sunny and Cherry models both made the top 20 in 1974. German brands were not that strong then, with Volvo the best of the premium brands.

70	71	72	73	74	Brand	1970	1971	1972	1973	1974
1	1	1	1	1	BLMC	398,281	498,306	528,694	512,350	400,898
2	2	2	2	2	Ford	285,720	240,937	401,994	376,213	288,394
3	4	3	3	3	Chrysler	112,590	135,229	153,765	161,656	114,121
4	3	4	4	4	Vauxhall	107,560	138,199	147,172	132,980	92,316
	15	9	6	5	Datsun		6,852	30,197	60,513	58,758
6	6	5	5	6	Renault	31,159	41,732	60,242	67,071	57,126
7	7	7	7	7	Fiat	23,476	36,205	47,606	50,687	43,609
5	5	6	8	8	VW	37,371	48,883	52,686	42,871	38,882
11	8	8	9	9	Simca	7,854	24,243	34,121	28,777	23,446
9	9	10	10	10	Volvo	10,471	15,476	19,911	22,828	17,708

BL again doesn't have Jaguar included, and what was is shown below:

Brand	1970	1971	1972	1973	1974
Austin / Morris	296,828	366,877	391,556	384,256	302,689
Triumph	64,036	86,533	91,928	90,712	69,224
Rover	25,223	31,508	30,035	23,627	18,488
MG	12,194	13,388	15,175	13,755	9,852
Unsure					645
Total	398,281	498,306	528,694	512,350	400,898

Data source: SMMT.