In the Age of Chaos and Dryads, Branchwraiths and Treelords were forced to try and fight off Nurgle and his attempt to conquer their realm, together with other forces of Order, mustering in the deepest of the Wyldwoods.
The war dragged on for centuries and slowly the realm of life and its inhabitants were first cut off from the other realms and then ground down by the forces of Nurgle. All seemed lost.
Then the Stormcast Eternals were cast down from Azyr to seek out the goddess Alarielle and ignite again the resistance against Chaos. Now reborn in all her glory, she leads a new war of life against the invaders.
The sylvaneth are guided and reassured by the Spirit Song, which Alarielle sang when she sowed the first soul-pods. It is more than a song, it is an enchantment that still flows through spirit and land alike, binding hem together and allowing communication across the realm.
Sylvaneth society is divided into a number of groups:
- Forest Folk: Dryads, Branchwraiths - previously peaceful spirits who tended the wild places of the Realm of Ghyan.
- Noble Spirits: Treelords, Branchwyches and Tree-Revenants, they are the Leaders of the Sylvaneth.
- Free Spirits: Sons of Durthu and Kurnoth Hunters, powerful fighters but they also speak with the authority of the goddess.
- Outcasts: Dangerous and vicious spirits who can only hear a part of the Spirit Song.
- Water Spirits: Some Sylvaneth have adapted to live in the seas and oceans. 
There are some Sylvaneth who have turned away from their goddess. Although Alarielle has first claim on their souls, as she faded in the Age of Chaos, they found a different lord in Nagash and they still serve him in the Realm of Shyish, [6a]
The Glades are the nations of the sylvaneth, although they could also be described as truely vast extended family. Like a family they share traits, traditions and culture.
- Dreadwood Glade: Even the other glade spirits do not trust those from Dreadwood, they are renowned as malicious, cruel and spiteful. 
- Gnarlroot Glade: The glade seeks knowledge and lore above everything and will ally with the scholars and sorcerers of other races to gain it. 
- Harvestboon Glade: Led by the Willowqueen, the glade spirits have a reputation for powerful magic and youthful exuberance as they were only created in the Age of Chaos. 
- Heartwood Glade:Worshipers of the god Kurnoth who they consider Alarielle's consort and unsurprisingly the first to welcome Kurnoth Hunters. 
- Ironbark Glade: Not only in Ghyran but a strong presence in the Realm of Chamon and have forged strong alliances with the duardin. 
- Oakenbrow Glade: The First Glade - their soulpods planted by the goddess herself, they have built a reputation for generosity and nobility but also so some claim, arrogance. 
- Winterleaf Glade: The Age of Chaos has devastated their once beautiful lands and their outlook is full of fatalism and introspection. 
- Royal Moot
- Spites: Diverse magical imps and creatures that spring up around the Sylvaneth, they can be whimsical, cruel, foolish and enigmatic. They assist the tree-folk in many little ways and they in turn indulge them in their playfulness and protect them.
- Greater Spirits
|Ardaneth||Sylvaneth||Branchwraith||Forest Folk||Once the priestess of the Arkenwood, she now accompanies the Spirit of Druthu Shaddock who is all that remains of her forest home.|
|Bramble-Maiden||Sylvaneth||Branchwraith||Forest Folk||An ancient handmaiden to Alarielle, sister to the Lady of Vines.|
|Lady of Vines||Sylvaneth||Branchwraith||Forest Folk||Handmaiden and bodyguard to Alarielle having served as a captain of war since the Age of Myth, carried her queen as a soulpod to safety during the initial part of the Realmgate Wars.|
|Brachylaena||Sylvaneth||Kurnoth Hunter||Free Spirits||The Gnarled and eldest of Huntmasters. He took part in the battle for the Genesis Gate.|
|Dollenhal||Sylvaneth||Spirit of Durthu||Free Spirits|
|Maesleir||Sylvaneth||Spirit of Durthu||Free Spirits|
|Oadenwul||Sylvaneth||Spirit of Durthu||Free Spirits|
|Shaddock||Sylvaneth||Spirit of Durthu||Free Spirits||Wardwood of Athelwyrd. He awoke in the Age of Sigmar to find the Arkenwood devestated by the power of Nurgle and quested through the realm to find Alarielle|
|Felyndael||Sylvaneth||Unknown||Noble Spirit||Guardian of the Waning Light, a Noble Spirit of the Heartwood Glade who fought in many conflicts during the Age of Chaos.|
|Haaldhorm||Sylvaneth||Treelord Ancient||Noble Spirit||The Wrathsinger of Clan Naeth'ar with a timeless hatred for the gods and minions of Chaos. The most ancient of the Sylvaneth.|
|Lharenthol||Sylvaneth||Treelord Ancient||Noble Spirit||A member of the Harvestboon Glade that forged an alliance with Drycha Hamadreth to take back Vastclaw Valley, freeing Eagderethil, the father of bladewillows.|
|Nellas the Harvester||Sylvaneth||Branchwych||Noble Spirit||A member of House Il'leath of the Heartwood Glade.|
|Sternbark||Sylvaneth||Treelord||Noble Spirit||A treelord that fought the Glottkin.|
|Drycha Hamadreth||Sylvaneth||Regent of the Outcasts||Outcasts||The regent of the Outcasts, Drycha is a dark spirit who has her origins in the World-that-Was and Alarielle was reluctant to plant her soul pod, only doing so during the darkest days of the Age of Chaos and then in the hateful chasm of Hamadrithil.|
|Kelara||Sylvaneth||Naereid||Water Spirits||The leader of the Naereids in the Sea of Serpents, she aided Alarielle in her flight across the frozen sea at the beginning of the Age of Sigmar.|
|Usniel||Sylvaneth||Lord of the Deeps||Forest Folk||The Lord of the Deeps and guardian of the great serpents, whose own tails reach into the very roots of the Realm of Ghyran|
- 1: White Dwarf Issue 76 11 July 2015, the Forces of Order.
- 2: Warscrolls
- 3: The Realmgate Wars: Balance of Power
- 4: Battletome: Sylvaneth
- 5: The Tainted Axe (short story) by Josh Reynolds
- 6: Soul Wars (novel) by Josh Reynolds
- 6a: Chapter Ten
- 7: From the Deep (short story) by Jaine Fenn
|Sapient Races of the Mortal Realms|
|Mortals||Aelf (Cythai • Scáthborn) • Ba'hal • Duardin • Fimir • Gargant • Human • Ogor • Slann • Spite • Sylvaneth (Forest Folk • Noble Spirits • Free Spirits • Outcasts) • Troggoth (Fellwater • Rockgut • Sourbreath)|
|Beastmen||Bullgor (Cygor • Ghorgon) • Centigor • Gor (Tzaangor) • Skaven • Ungor|
|Greenskins||Grot • Orruk • Snotling|
|Undead||Malignant • Mordant • Reanimant (Morghast) • Skeleton • Vampire|
|Daemonic||Seraphon (Chameleon Skink • Kroxigor • Saurus • Skink) • Chaos Daemons (Bloodletter • Bloodthirster • Chaos Fury • Daemon Prince • Daemonette • Gaunt Summoner • Great Unclean One • Horror of Tzeentch • Keeper of Secrets • Lord of Change • Nurgling • Plaguebearer • Soul Grinder • Verminlord)|
|Other||Dragon Ogor (Shaggoth) • Kelpdar • Merwynn • Sankrit|