The author's choice of the word "herded" has a significant impact on the excerpt and helps to create a vivid image of how the deportees were treated during this process.
The word "herded" implies that the deportees were treated like animals, without any regard for their dignity or humanity. The word creates an image of a large group of people being forcefully and aggressively pushed along, possibly by guards or soldiers.
Furthermore, the use of the word "herded" suggests that the deportees had no choice in the matter and were being controlled by others, making their situation even more tragic and heartbreaking.
Overall, the author's choice of the word "herded" helps to emphasize the cruelty and inhumanity of the deportees' treatment, and creates a powerful image that enhances the emotional impact of the excerpt.