Seikai no Monshou

Both based on novels. The two main characters and their relationships are also the similar. The main plot is about the main couple's journey. The mercantile overplot of Spice and Wolf is very similar in scope to the interstellar warfare overplot of Seikai no Monshou. It may not seem like it at first glance but Seikai no Monshou is pretty much Spice and Wolf in space and Spice and Wolf is Seikai no Monshou in late medieval europe. 

The first thing that one will note in watching these two shows is that on the surface, they seem to have nothing in common. One is a space opera, and the other is about a traveling merchant. The true core of each of the shows though is the relationship between the male and female leads, and in that sense, the shows are very compatible. Both shows are rather slow paced, and do a great job of developing the main characters and their bond along their travels. Spice and Wolf sees Lawrence accompanying Holo on her journey to the northern homeland, while Crest of the Stars follows Jinto as he goes a long with Lafiel back to her home planet (and in a larger sense accompanying her on her journey to become empress). Both Holo and Lafiel will also have to eventually come to terms with the fact that their own lifespan will greatly extend past those of their respective male companions. read more 

This is a one-way recommendation. Those who enjoyed Spice & Wolf are likely to enjoy the Banner of the Stars series, but not necessarily vice versa. The relationship between the two main characters is an integral part of both series, although it is not always what drives the plot in either case. Similarly, a great deal of attention is given to dialogue in both cases: In Spice & Wolf this almost exclusively comes in the form of competitive banter and wittiness. However, in Banner of the Stars the banter between the main duo tends to be less competitive and there are more genuine discussions. On these merits alone one might be able to recommend in either direction, but the primary distinction between the two anime is their usage of their setting. Although the setting of Spice & Wolf is well designed and occasionally plays into the events of the plot, the setting of Banner of the Stars is far more relevant both to the relationship between the two leads and to the events of the story. That is, in Spice & Wolf any conflict can almost always be pinned on one of the leads, whereas in Banner of the Stars larger cultural conflicts have both direct and indirect effects on the leads. Because of this, the way the leads' interactions relate to the greater narrative context won't feel the same (which is to say there is very little greater narrative context in Spice & Wolf). At that, many may find the cultural conflicts of Banner of the Stars to be easier to digest than the economics of Spice & Wolf. It is for these reasons that I mostly consider this a one-way recommend, with the inverse being recommended only cautiously. Action is more prevalent in Banner of the Stars than in Spice & Wolf, but like Spice & Wolf, you will likely be bored if you're only coming for the action. Finally, although neither anime series covers all of the source novels, the ending of the Banner of the Stars series is far more conclusive and satisfying than the ending of the Spice & Wolf series. In fact, it is very likely that those unaware of the Banner of the Stars novels wouldn't realize the novels were still ongoing in the first place. In the end they are both excellent series with similar positive traits, but I consider Banner of the Stars to have broader appeal and better cohesion between the characterization, setting, and themes. If you liked the former, be sure to check out the latter. read more 

Romance between a normal human and a non-human that develop over time, through their long journey together. Both male leads and female leads are characterized by a strong sense of pride, and a high level of intelligence. Much of the screen time is occupied by the witty dialogue between the couple, but there is enough interesting contents in the dialogue that it never gets old. 

Both Spice and Wolf and Seikai no Monshou (including Seikai no Senki I, II & III) are as much about sociology as they are about the main characters. If you liked Spice and Wolf's slow sightseeing pacing punctuated by bursts of actvity and its slowly budding romance, you might enjoy this space opera-setting journey. 

The relationship between the two leading characters in each anime is similar: -there is a slow, natural-paced blossoming romance (with no typical shoujo complications owing to a 3rd rival or the like) -they have to come to terms with the issue of race; the female in both cases will live long after the man dies of old age. There are also many cultural differences at first. -there is a LOT of dialogue and witty banter between the two. -they are both travelling together throughout a vast land/space 

Both similar in that the main focus of the story is the developing relationship between the two main characters. The two leads both talk about their feelings, talk through how to solve the problem at hand, and talk about themselves. Unsurprisingly, in the midst of all the talking a connection forms. Ookami to koushinryou is set in a background of medieval travelling merchantry, while Seikai no Monshou is set in Space. Both have the two characters coming to understand their differences t due to different upbringing and culture.  

They both have absorbing conversations between the characters, and the two lead characters have a brilliantly fleshed out relationship.  

Great couples in both shows,slow paced a lot of dialogues  

What makes spice and wolf what it is it's character interactions between it's main characters and the closest thing you can find is Crest of the stars.  

Two of the best space-opera anime ever created. Both are heavily focused on a gigantic war, politics, and have a large set of characters (even though the Sekai series are more focused on the Jinto/Lafiel relationship). Both are also adapted from best-selling novels. 

These are space operas about ships and people, so you'll like either, though LotGH is a bit broader in scope while SnM deals with the main characters in a more personal matter. Also, each episode starts with an old dude talking about a planet or government. 

Those who've started from Crest of the Stars will most likely find Legend of Galactic Heroes quite appealing. These titles have lots in common including global wars, tactics and politics from one side and great attention to individual experiences from the other, what makes them both feel like epic sagas. Crest seems to pay tribute to LoGH in many ways, while being more idealistic and childish in a good sense. It has a fantasy feel with Abhs being space elves. LoGH is like more "down to earth" and historically oriented. 

Both are epic (when including the sequels of Seikai no Monshou) space-operas in an immersive, militaristic Sci-Fi world where autocratic/feudal and democratic factions are in endless wars. LotGH targets a more mature audience and is "dryer" because it intentionally presents itself as historical record. SnM is more emotional, as it has focus on a couple and their romance and the dramatic scope is lower (planets vs. the whole galaxy). Both have individually portrayed military brass, youthful male and female protagonists, and large scale strategic battle scenes. Both have a fascist undertone which justifies "the end justifies the means" and "might is right" thinking, where LotGH is more reflected about it and SnM bluntly right-wing. In a nutshell, SnM is the emotional version of LotGH showing only the imperial side of the war. read more 

Both deal with complex relationships between two races with a sci-fi space motif. Furthermore, the focus of both shows lies in character development rather than action, but when there is action, it is well done. 

Space operas with a focus on sociology. 

Space operas by the same studio, both were made around the same time; both feature large-scale political engagements, romances, and similar soundtracks. 

Space. People. Multiple people. Humanoid races battling each other. What's not to like?