If you can handle watching a very long drama of 134 episodes (1hour long each) then I'd highly recommend this drama. It's a long drama but it never drags or prolongs things. It moves from one situation to another and the flow is very good and well paced. It took me over 2 weeks of straight marathoning it to complete it.
The drama is about the life of Dae Jo Yeong and his quest to recapture the old Goguryeo and create an empire that embraces all people from all origins (Baekjae, Goguryeo, Khitan, Silla, Mohe, Turks ectra...). It's about the founding of the Kingdom of Balhae. And all the heroes that were involved in its rising: Dae Jungsang, Dae Jo Yeong, Gulsabiwu and countless others. This drama does not lay heavily on facts (just take a look at Wikipedia and you'll know lol) - many of the characters life, death and even existence is quite fictional - but it made for a great story. One, the two main females don't even exist in reality :P Some sites say that the two rivals in this drama, Jo Yeong & Kaigu (Hae Gu) vie for the love of the two leading women - but that's simply not true. There will be two romances for Jo Yeong (one that never should have been and one that was always right) but as for the other guy, he only looked at one woman.
Cast/Characters: My all time favorite character was played by Choi Chul Ho as Gulsabiwu (one of Jo Yeong's sworn brothers). I adored him so much, out of all the characters in this drama I would marry him ^_^ His character was very loyal and faithful - a true friend/brother. He had an unending passion and determination to not let the enemy defeat him and when teamed up with Jo Yeong and Sudol he was unstoppable ^^ (I'm also a fan of this actor and I love it when I get to see him as a good guy so my heart can freely go "gaga" over him lol).
Dae Jo Yeong played by Choi Soo Jong - he is the reason I decided to watch this drama, I've been a fan of CSJ since I first watched him in 'Into the Flames' (his latest drama and I started backtracking all his dramas since then). I always like him in leader type roles as he plays them exceptionally well (Dae Jo Yeong, The Great Kings Dream, Into the Flames, Comrades, President, and more...). I always admire his characters and would follow his leadership without a doubt. His character in this drama was exactly like that: one you can trust and depend upon. His character is full of love and passion for his people. He pursued his dream of recapturing the old Goguryeo not for his own selfish desires but b/c it was not only his dream but his peoples dream. He once quoted: "One man's dream may end a dream, but a dream that we dream together always comes true." He was a man full of love, honor, and selflessness.
Kaigu played by Jeong Bo Seok was a man full of envy, hatred, greed and a thirst for revenge. His "dream" was out of selfish motivation. He only loved one woman but b/c of that also spurred him to hate Jo Yeong even more, as he felt what was his was taken. I kind of got tired of his "I'm angry" face as it felt extremely forced and uncomfortable.
Suk Yeong played by Hong Soo Hyun was the girl I liked in this drama and the one who I believed was always right for our lead character. She had a selfless heart, full of love and compassion just like our lead. They were very well matched. And I wish our lead had only had eyes for her for the entire drama but whatever... lol. She reminded me of Seo Ji Hye's character from 'Kim Soo Ro' b/c of her love that went unnoticed for awhile b/c his eyes were directed elsewhere - but eventually they look to the right one.
Chulin played by Park Ye Jin, I did not like her at all. I wish she would have stayed where she belonged b/c it was a love that I personally believed was very wrong - you cannot be lovers with someone that you are helping to destroy. Opposite sides cannot be together, it can only end badly and you could even make things worse. I couldn't believe that our lead guy didn't realize that. She would have been a decent character on her own but b/c the writers made her this way made me unable to ever like her.
Geom played by Jung Tae Woo (an actor I've started to really like since I first saw him in 'Comrades') comes on in the latter part of the drama (I think around the 80ish episodes) was a great addition to the casting, I really liked his character, even though you end up feeling so bad for him b/c of how torn he is and you can literally see it eating him up. But your heart will surly move for him. A great actor who really deserves lead roles! He always seems to be stuck doing "Supporting or guest roles" and I think that is just not fair to this actor who is so talented (I mean unless it's his choice but I don't think that's so).
And there were tons of other characters that shined but I obviously can't describe them all lol but I'll list there names: Mimosa, Geumlan, Dae Jungsang, Keum Mo Jang, Dae Dan, Yang Man Chun, & King Bojang. Heuk Sudol was a great friend but I wasn't too keen on him b/c outside of his friendship he was kind of a numbskull and drank too much and when he bickered or raised his voice I got annoyed. But I enjoyed the bromance between him and Gulsabiwu & Jo Yeong.
Music: Throughout the entire drama it's just instrumental music. The lyric songs came on during the credits (but who sits and watches those unless it's airing?) so the first time an actual song played was in episode 128 (the ending) by Park Hyo Shin (and you'll cry). And then a little later another song is played a couple of times but more as background music. Songs: Park Hyo Shin 'Ae Sang/Sorrow' (it was played in a very appropriate scene). L. Woo & Sung Ho 'Before the Break Up' (I actually don't remember where this was played in the drama) and Joo Byung Sun 'Mothers Land'.
Also you may have to bear with the first 7 episodes as it's all about the older cast - I was quite bored during those episodes b/c they didn't have anyone I wanted to look at lol - the main cast doesn't appear until episode 8. Also if your like me you might hate the first romance. I almost dropped this drama during the span of episodes 40-50. After that I had no desire to drop it though - so if you reach that point just press through (skip watch if you must) and it will get much better ^_^ I personally skipped most scenes about the Empress of Tang and Xui Rengui (since it was things I pretty much already knew about anyways).