Sentences consisting of only a long attribute and a noun


Take this one from [天狗 -
Wikipedia](https://ja.wikipedia.org/wiki/%E5%A4%A9%E7%8B%97) as an example:

> 飛鳥時代の日本書紀に流星として登場した天狗だったが…

  1. Is it the same as

天狗は飛鳥時代の日本書紀に流星として登場したが…

  2. Why do you use `だった` instead of `だ` here?

Thanks in advance.




>   1. Is (A) 飛鳥時代の日本書紀に流星として登場した天狗だったが the same as (B)
> 天狗は飛鳥時代の日本書紀に流星として登場したが?
>

Although (A) and (B) are logically same, Tengu is emphasized more in (A) than
in (B), and as a nuance, I feel, they are quite different.

(A) 飛鳥時代の日本書紀に流星として登場した天狗だったが…  
_It was Tengu that appeared as a meteor in Nihon-shoki (the oldest chronicles
of Japan) in the Asuka period, but now it is just a legendary creature with an
unnaturally long nose._

(B) 天狗は飛鳥時代の日本書紀に流星として登場したが…  
_Tengu appeared as a meteor in Nihon-shoki (the oldest chronicles of Japan) in
the Asuka period, but now it is just a legendary creature with an unnaturally
long nose._

>   2. Why do you use だった instead of だ here?
>

Since the time when the Tengu was thought to be a meteor is a past or the Aska
period, it is expressed in the past tense.




>   1. Is (A) 飛鳥時代の日本書紀に流星として登場した天狗だったが the same as (B)
> 天狗は飛鳥時代の日本書紀に流星として登場したが?
>

Although (A) and (B) are logically same, Tengu is emphasized more in (A) than
in (B), and as a nuance, I feel, they are quite different.

(A) 飛鳥時代の日本書紀に流星として登場した天狗だったが…  
_It was Tengu that appeared as a meteor in Nihon-shoki (the oldest chronicles
of Japan) in the Asuka period, but now it is just a legendary creature with an
unnaturally long nose._

(B) 天狗は飛鳥時代の日本書紀に流星として登場したが…  
_Tengu appeared as a meteor in Nihon-shoki (the oldest chronicles of Japan) in
the Asuka period, but now it is just a legendary creature with an unnaturally
long nose._

>   2. Why do you use だった instead of だ here?
>

Since the time when the Tengu was thought to be a meteor is a past or the Aska
period, it is expressed in the past tense.

