In order to gain a desirable wide back, you have to perform the most vigorous exercises which are the powerlifting mass building routines. The deadlifts, the Squats and the Bench.
To highlight your back, you must make mass all over first and lose some body fat. If you are willing to do the work and you are a healthy athlete, I highly recommend the conventional and snatch grip barbell deadlifts combined with the barbell squats and overhead pressing. Later you can add some power cleans and extend the program to Olympic lifts.
As assistant exercises, I also like the heavy tire flipping, sled pull/push and heavy barbell deadlifts from the rack. These movements are all compound exercises, and for the more advanced trainers, there are many body weight and body part, isolation exercises available as assistance exercises after you build a good foundation.
My trainer prefers the strength training, Powerlifting and Weightlifting multi-joint exercises. For the absolute starters, the new trainers, I recommend building lean muscle mass all over using these Powerlifting exercises and then combine your program with an added focus on the deadlift variations.
Deadlifts, if done properly with proper progression programming - will create a chiseled mass on your posterior extending from upper traps to lower back and stretched to your core, hamstrings, and legs.
The Wide-grip deadlifts indeed impact your posterior with extra emphasis on upper traps producing a robust and broad back.
Your weightlifting volume, intensity, and frequency, genetics combined with proper nutrition and recovery ability are the essential factors to build the beast look.
All the best...!